Canyoneering Gear
Section 18
Listed on this page are what is required to go Canyoneering. The essentials are a core part of the gear, too. Essentially gear that you would normally bring on a hike, this is what you bring canyoneering too.. This is NOT an exhaustive page. This will allow you to do most canyons found on the Colorado Plateau.
So in order to descend technical slot-canyons, you will need to carry the following items. These all play a vital role in your safety. Remember, safety is always first, followed by second, your enjoyment. If you are not having fun descending slot canyons, then why even do it?
The "essentials" is what provides the platform for all canyoneering. If you ever get invited, then the assumed by the hosting party is that you will bring THESE. If you don't have ALL of these, then you are insufficiently prepared to descend and will be the "weakest-link" in the group or biggest liability. Please don't jeopardize your life or your parties group (or yours or their enjoyment) by not bringing these things.
Required Gear:
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Helmet
-
Harness
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Descender Device
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Rope
-
Pull-Cord
-
Rope Bag
-
Minimum of 3x Carabiners
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Backpack
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Personal Anchor System (PAS) | Safety Tether
-
Canyoneering Shoes
Essentials:
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Slings
-
Booties & Socks
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Gloves
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Dry Bag or Keg
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Headlamp
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Water Container
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Sun-screen
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Lifestraw (water-filter)
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Map (& GPS)
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Extra Clothing & Light Jacket
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First-Aid Kit
Required Gear:
Helmet

Image Credit: Brett Johnson (C)
From what I have noticed in my 18 years of canyoneering, is that most canyoneers prefer the Black Diamond Half-Dome helmet. This isn't an endorsement, but for some reason they just choose that. They retail for approx. $60. I personally use it too.
Not too long ago, people made fun of each other for wearing helmets! Whether it was on a motorcycle, skateboarding, and biking just to name a few. Thankfully, that didn't last too long and now it's the cool thing to do. It really is!
It goes without saying, but it must be said, that you HAVE to protect your head! In canyoneering, you will be rappelling and down-climbing in some precarious situations and at any time, pieces of the cliff above you (or even the next rappeller in line) could possibly drop small (and big rocks) on you! Imagine rappelling on a hundred foot cliff and the people on top of the cliff are unwittingly kicking golf-ball size rocks right towards you! A helmet will protect your head in this case! It may still hurt and leave a bruise too but better than having an emergency.
Another thing, you may be the best parkour person out there who is mindful of every step and will never let a rock fall! So you may be able to control what YOU do, but you CANNOT control what others do or don't do. It's to protect your head even when others are not being careful around you.
Any rock-climbing helmet will do (or even a biking helmet would suffice). Most helmets are unisex, although some brands do offer the different sexes version but they have subtle changes. Please spend the money and invest in one!
Harness

Image Credit: Brett Johnson (C)
Any climbing canyoneering harness will work. There isn't a specific canyoneering harness that I'm aware of.
You can skimp on the money here and get the cheapest one you can find, but it will lack in comfort. But if you plan on doing Canyoenering for the long run, I spend more money for a more fitted and comfortable harness (which essentially is padding around the waist and leg loops).
I personally use the "Momentum" model by Black Diamond. It has adequate comfort on the legs and hips which is important for long rappels (above 100 feet), can easily be worn for long periods of time without discomfort, has two "gear loops" (where I can attach extra carabiners and gear), and of course the all important belay loop (typically, the colored loop) in the middle that ties the waist strap and leg loops together.
Again, any harness will do the trick but the rest is up to you when it comes to comfort and style (or color).
I would suggest going to a climbing store (such as R.E.I.) to try one on before you buy it, especially before you do an online purchase. Harnesses can be found in male and female sizes and typically range between $40-$120
Descender/Rappel Device

Image Credit: Brett Johnson (C)
Descender (or Rappel) Device is the generic term for the mechanism that attaches you from the harness to the rope. There are over a dozen in recent memory that climbers and canyoneers use. In Canyoneering, it's best to buy one that has the option to add more friction on-the-fly and can allow you tie-off (or stop) while rappelling. The ATC and Figure 8, while good for short rappels (less than 50ft) are not great for longer rappels as you cannot add friction to slow you down or tie-off easily.
Over time you will understand that choosing the "right one" does come down to comfort level. All are generally "safe" and each has their pros and cons.
I personally use the Bluugnome.com descender device called the "SQWUREL". It allows me to rappel while having the ability to add more friction, which is important for controlling your descend speed. However, it does have the affect of "twisting" the rope. So, it is important to untwist the rope before the next rappeller goes.
A typical "Figure 8" descender "twists" the rope too. Meaning, that when you get to the bottom of the rope, there is going to be a lot of twists that you will need to straighten out. Think of the "twisting" similar to a water hose that you are trying to coil up. Once the water valve has been turned off and you bleed the extra water from the water sprayer, it is much easier to coil up and rather neatly too. If you do not bleed that extra water, you will understand how hard it is to coil the water hose. In the canyoneering sense, this "twisting" of the rope is very similar of trying to coil that water hose that hasn't been bled out. There for you will fight the hose in trying to coil it up. If you don't untwist the rope, the next rappeller will have a less pleasant and not as smooth experience. In fact, if the twisting is so severe, it may even prevent the rappeller from going down!
Most Canyoneers now using the CRITR2, SQWUREL, or ATS as the primary descender device. The ATC is still used by many but it's more generally used on short rappels due to the device not being able to add friction or even stop (aka "tie off") while on rappel.
Best practice is to bring TWO descender devices on every trip per person. The primary reason for this is to use the second as a backup, in case one drops it over an edge or in the water, or someone forgets to bring theirs (which happens surprisingly enough to be an issue in large groups).
Before buying one, The MOST important thing you can know about the your specific descender device are these questions 1) can you add friction while on rappel? 2) can you stop (aka "tie off") while on rappel? Refer to your manufactures manual for more information on that and refer to the online canyoneering communities for specific instruction.
Once it is bought, please, please, find a low-angle practice rappel area in your area and know how to work that descender/rappel device very efficiently. Using it for the first time in a canyon without the knowledge of how it works properly is unwise and potentially unsafe.
Rope

Image Credit: Brett Johnson (C)
While hiking the canyon is the primary of how you go through the slot canyon, most people look forward to this other aspect - the rappelling. While I don't think it's the crowning jewel of the sport, it is a means to an end. Most people have a healthy fear of heights and rightly so. In canyoneering, most cliffs or drops cannot be bypassed, and thus, will need to be rappelled. This is where ropes come in to play. Ropes can have additional purposes such as being used as a hand-line where drops are short enough where a rappel isn't necessary and can also help raise or lower gear.
Ropes come in many shapes and sizes, however they are not all created equal! First, and most importantly, DO NOT buy rope from a home hardware/building store.
You need to buy a RATED rope from an actual climbing-oriented company. The ropes in hardware/building stores are not tested or used for climbing or rappelling. In fact, some ropes and carabiners explicitly say "NOT TO BE USED FOR CLIMBING". Great advice! Do not use those to trust your life to! (But, they could be used to attach non-essential gear to such as cameras and water bottles.)
In canyoneering, we specifically use a static rope. There are two types of categories or ropes: dynamic and static.
Dynamic ropes have energy-absorbing properties built-in to them to absorb the energy from a fall (if a rock-climber is to fall from a height).
Static ropes have very little "bounce" to them, thus will not absorb energy from a fall if you were to rock-climb with it. They also do not absorb water or become water-logged,will create a more smooth rappelling experience, and can be light in weight and thickness (or diameter).
CAUTION!! - if you use a thin rope size diameter, such as 8 mm, you will need to properly adjust for the correct "friction level", especially given your body weight. The more mass you have, the more friction you should add!
This friction level all depends on your body weight, length of the rappel, and what kind of descender/rappel device you are using!
For example, if you were to use an 8.0 mm rope for a long rappel (above 150+ ft), then be prepared to rappel down almost uncontrollably, especially if it is your first time rappelling and do not understand! And if you are not careful enough or can't brake yourself while on the rappel, then you will 'crater" to the ground and get injured or even die.
It is extremely serious that you understand this concept.
MY OPINION is that beginners should be using 9 mm ropes until you can master the art and science of rappelling safely (especially for heights that are 200+ feet). Smaller ropes such as the 8.3 mm (or even 8 mm) should be used with caution and only those who know how to add friction while rappelling.
I personally use the Imlay Canyon Gear "Canyonero" 9 mm rope. It's been a great, reliable rope that has been through many canyons, sand, water and cliff edges. I also own a 220 foot Imlay Canyon Gear 8 mm "Canyon Rope" for when weight and bulk matter.
In my possession, I have other sizes of ropes that vary in lengths (because sometimes a canyon's tallest rappel is 60 feet and you don't need to haul around 130+ ft of extra rope.
If you are just starting in the world of Canyoneering, I would suggest two rope sizes: a 120-foot 9 mm static rope and a 210-foot 9 mm static rope.
120 feet will get you through a majority of slot canyons on the Colorado Plateau.
In addition to the the shorter rappel rope (120-feet) and depending on the canyon, you will also need to carry what's called a "Pull-cord" to retrieve your rappelling rope. See below for more information on the "Pull-cord".
Pull-Cord

Image Credit: Brett Johnson (C)
A pull-cord is necessary when your rappel rope is shorter than when you can double up the rope.
Let me give you an example. So, you read about a canyon that has a maximum rappel height of 115 feet. One option is to bring a 300 ft rope (which is a LOT of rope) so that you can "double it up", meaning that you rappel on 150 feet of the rappel and use the other 150 feet to pull the rope down from the anchor on top. This way you can RETRIEVE your rope and carry it through the canyon.
But, that rope weight alone is going to be 12.9 pounds (a "9.2mm Canyonero" rope @ 4lbs 3.2oz per 100ft) and require a big backpack just to carry it. Don't forget that you also need to carry your other canyoneering gear too in that backpack. To add more stress, then you will have to navigate canyon obstacles, and hike miles for the approach and exit...
- OR - you can bring a "pull-cord", which in essence is just a smaller-size diameter rope to "retrieve" the rappelling rope.
All ropes in canyoneering should be bought as a static and NOT dynamic. Static means that the rope DOES NOT stretch when loaded. A canyoneering specific pull-cord is no-exception. The set community standard size is 6 mm. (Although, technically, any rope can be a pull-cord).
In the above example, bringing a 200-foot pull-cord instead of a 300 ft rappelling rope, you are looking at a total weight of 2.1 lbs just for the pull-cord. Then you add on just 115 feet of rappelling rope (the 9.2mm Canyonero rope) for 4.5 pounds. So your total weight for carrying 115 feet rappel rope and 200 feet of pull-cord is 6.7 lbs. That's 2 lbs lighter. This figure will go up on the bigger rappels.
The other big, additional advantage is that there will be LESS bulk in your backpack. Now you can carry the 115 ft rope, wetsuit, 3-liters of water, dry bags, food, and other canyoneering goodies all in one large backpack.
Rope Bag


Image Credit: Brett Johnson (C)
Image Credit: Brett Johnson (C)
A "rope bag" is...you guessed it...a bag for your rope (and/or pull-cord). You can get by without using one, but the advantages of having one outweigh of not having one.
You may see people hiking with ropes that are attached to the outside of bags. There is one good case where this is acceptable. That case is when your backpack is too full with other essential-travel or canyoneering gear BUT still need room for your rope.
The problem with dangling rope on backpacks is that if they are not tied properly for rope-hanging, then the rope concoction that you tied will fall apart as you hike towards your canyon possibly wasting hiking time. It could also create knots or twists as you swing the backpack around and climb over obstacles, and get snagged on bushes or trees (which you will be going through a lot in canyoneering). This could create a dangerous situation either in your personal safety or the possibility of not realizing the rope fell off hiking to or from the canyon. (Although you could mitigate that by having the rope person NOT be the last person in the group).
Using a rope bag keeps the rope ready for easy deployment at rappels.
For that deployment, when you are at the rappel, just attach the rope bag to a carabiner on an anchor point and then you won't have to worry about it dropping accidently before it is connected properly.
On the pull-cord side, we do not throw the rope bag until the last person is ready to rappel. This will "keep it simple" for everyone in your party by 1) knowing which strand of the rope to rappel on (critically important!), and 2) it won't get twisted in with the rappelling rope which could create a possible dangerous situation for the person rappelling.
When you toss your rappel rope down in a rope bag, a big benefit to having it all consolidated in one bag will allow you to hear the loud "thud" as the rope-bag hits the ground. This will audibly tell you that indeed the rope is long enough for that rappel. I'm willing to bet that those who do not use a rope-bag statistically have more "close calls" or "issues" with the rope since they cannot hear the rope hitting the ground as easily and so more checking and adjusting the rope is necessary. I hear on Facebook and videos on YouTube about people who go through canyons having to readjust the ropes or not knowing if their rope touched the bottom and having to ascend back up because they forgot to check etc.
If you don't hear that thud, then the rope got snagged somewhere on its way down, or even worse, the rope isn't long enough!
One obvious important note and will be stated for emphasis - having a rope that isn't long enough for your longest rappel will have life-or-death consequences! Be warned and plan well in your canyon research!
Carabiners

Image Credit: Brett Johnson (C)
The most common of gear among Canyoneers is the carabiner (pronounced: care-a-bean-er). This load-rated (very important!) metal device acts as a coupler that secures you or an object to another object. They come in MANY sizes, shapes and ratings. The most important thing here is to get one that is RATED. How do you know if its rated? Check for printed or etched writing anywhere on the carabiner (typically the "spine") that says the words "kN < > 17 "
"kN" is abbreviated for kiloNewton. Approximately 225 lbs (technically 224.80 lbs) equals 1 kN. This next part is imporant because we want to be calculating for "force" and not just weight. Force = Weight + Acceleration. This is important because during a fall, your body is speeding up (or accelerating) MULTIPLIED by your static weight (or mass). So lets say you fall for 1 second because there was too much slack in the rope. Terminal Velocity (the maximum speed you can free fall is 122 mph on Earth without accelerating). So lets say you weigh 200 lbs, free fall for 1 second, so what would the force be in kN so that your carabiner can withstand that force? At one second, you are falling at 9.8 meters/second. (Two seconds would be 19.6 m/s). So doing the calculations now... figure it out? That's a lot of force is all what I will say to that.

Image Credit: Brett Johnson (C)
Canyoneering Backpack

Image Credit: Brett Johnson (C)

Image Credit: Brett Johnson (C)
How is a canyoneering backpack different than a regular backpack? To the casual eye - not a whole lot. Ultimately, they all have the same goal - carry your gear. Carry your helmet, wetsuit, harness, ropes, quick links, descender devices, 3 liters of water, food, first-aid and misc.
But how they perform, is what the difference is. Most hiking backpacks are made from a durable (but not that durable) nylon and/or polyester mix versus canyoneering backpacks that are made from a canvas polyester mix. The difference is that the canyoneering backpack will hold up better for the long term. A sharp rock can make a big hole in a hiking backpack quite easily. But not so easily in the canvas backpack.
One other big difference in canyoneering backpacks is that they have some time of mesh or grommets located at the bottom which allow it to drain water quickly.
When you have a hiking backpack and you go through a watery canyon, when you try to stand-up, all of that water will be contained now adding 8-24+ extra pounds! (One gallon equals 8 pounds!). A canyoneering backpack with those grommets allow it to drain within a matter of seconds.
Some canyoneering backpacks have specific gear and helmet compartments which helps keeps gear organized and readily accessible.
Other canyoneering backpacks have none of those features except being completely waterproof. There are no ways of keeping things organized, but all of the contents on the inside are completely dry.
If you are committed to canyoneering for the long haul, please purchase a specific canyoneering backpack.
If you are doing just "The Subway" hike in Zion or got invited to do a technical canyon with a group, then sure, a simple large hiking backpack will work just the same in this case. But it will endure a lot scrapes and cuts. It won't be in pristine condition when you are done.
Personal Anchor System (PAS)
or "Safety Tether"

Image Credit: Brett Johnson (C)
A Personal Anchor System (PAS) is another critical piece of equipment that the canyoneering-community has standardized. It is essentially a sling or a closed-ended loop that attaches to your harness AND to the anchor rigging. Other people may call this a "safety tether", which is precisely correct.
In Canyoneering, you live on the edge (yea! hardcore!) And many of these edges are rappels that drop from 20 feet to 300 feet. You have to be safe!
This necessary tool allows you to be tethered into the anchor rigging while you work with your rappelling ropes to get them ready for rappelling.
If you were to slip while not clipped in, it would result in grave bodily harm or death.
One of the last physical steps you perform before rappelling is to remove your PAS.
Canyoneering Shoes

Image Credit: Brett Johnson (C)
Yes, there are shoes specifically for canyoneering! That's great, as durability, traction, and ankle support are what we need. Having the proper way shoes for canyoneering will almost be a literal night and day difference when you are walking on sandstone, and trying to work your way out a pothole.
Sure, sneakers or old gym-shoes may work for only the easiest, shortest canyons or once a year canyon trip, but if you plan on doing this for the foreseable future - please invest in some canyoneering shoes. The first canyoneering shoes were made by Five Ten, but since then a few more companies have developed a more canyon specific shoe. On the "Quick Facts" page, I have listed some of the most common shoe types that you can decide on. My preference are these Five-Ten Canyoneer3 shoes. Incredible ankle support and I can walk up slickrock areas where other shoes cannot. Unfortunately, Five Ten (which has now been bought out by Adidas) stopped making the canyoneering shoe back in 2018. If you can find them online, that's great. They are a top-notch shoe that is hard to beat. But most likely you will be paying more than $200 for them.
Now, buying the "right" canyoneering shoe has now become a little more difficult with companies discontinuing their hydro shoes.
Rock climbing shoes or Chaocos are not appropriate for canyoneering as you need ankle support, incredible grip, and something that can keep your feet protected and warm. You can wear those if you have been canyoneering for a while and know your likes and dislikes, but please don't wear those for your first canyoneering trip. Your feet will hate you and you will not have the appropriate grip if it's needed.
On other note about canyoneering shoes is that we wear these with neoprene booties/socks. And with that in mind, we buy shoes that are a 1/2 bigger so that it fits the extra neoprene perfectly.
Canyoneering shoes range between $80-$200.
Essential Gear:
Slings

Image Credit: Brett Johnson (C)
A sling's purpose is similar to a P.A.S. (see above) that attaches you to anchors, to climbing equipment such as handled ascenders or tiblocs, pothole escape equipment, and can also be used for other unplanned circumstances (lowering backpacks, tieing some of them together when you just need a little extra length).
They run between $10-$30 piece, so two or three is all you need.
Booties & Socks

Image Credit: Brett Johnson (C)
"Booties" are what we call neoprene socks. We wear them when we do wet slot-canyons so that we can keep our feet warmer (and functioning) while cold. Being cold in a slot canyon, with no direct-sunlight for what could literally be hours should not be treated lightly! So, to the tourist, while we are decked on with our wetsuits and booties in the middle of the summer, they have no idea that the canyon we just got out of has that type of cold water! In fact, in an unbeated canyon in Arches National Park, some friends and I were in wetsuits in May and we walk back to the trailhead and this guy asked us, "why are you guys in wetsuits? And...this is the desert! Where is water at?" Little did he know the adventure we just had.
I personally recommend a neoprene bootie that is 3 mm in thickness. You can find ones that are 2 mm and they still will do an adequate job, but 3 mm seems to be the thickness that everyone else agrees on too.
When there is no expected water in the slot canyons that we are visiting, I will wear marino wool socks instead of booties, because they provide extra cushion for the shoe, and in case there is water, wool does a decent job in keeping you "warm" when wet. In fact, that's one of the properties of wool.
I can hike with the extra heat in my feet for long periods of time, but I know that others are not. May I suggest bring a hiking sock for the approach hike and exit, and a wool sock just for the canyon? It may be slightly overkill, but come to think of it, either way, you'll have a dry pair of socks for the long hike out.
Check out the Quick Facts page to see what brands and types I have seen the community wear.
Gloves

Image Credit: Brett Johnson (C)
Gloves are not absolutely necessary for canyoneering, but once you have been through a few, you will see the importance.
Canyons will be tough on your gear, clothing and body! They in fact will be probably the reason of some of your most exhausting days of your entire life! I have had a few of those! And so trying to prolong our bodies is important, especially the part that we use the most - our hands.
Pictured above, I have three gloves that I will take into a canyon. The rubber-dipped black gloves provide general protection while in the canyon. I use it to climb up or down, moving bushes or branches out of the way, and while stemming and squeezing through the slot to give me more leverage as I move forward.
The thicker gloves are used for when I rappel on big (150+ foot) rappels. Tom Jones says that wearing gloves hides the mistakes of the rappeler. And to that, I definitely agree. The glove absorbs the heat from your hand as the rope feeds through it, which tells us that you are probably going to fast for the rappel. And that tells us that you do not know how to properly adjust your friction levels! There have been numerous accidents of people losing control on rappels and injuring themselves severely or dying. No one knows the exact cause, but witnesses typically say that they "lost control" while rappelling. "Lost control" means that they were going to fast and didn't know how to stop or add more friction (PLEASE KNOW HOW TO DO THIS!) to your rappel, and didn't have a bottom fireman's belay being used.
So beginners, please refrain from using gloves while rappelling until you can master the friction settings on your descender/rappel device! Other than the rappelling with gloves part, gloves in canyoneering are good.
Any leather glove (I prefer deer hide) will work, along with gardening gloves that have been dipped in rubber.
Dry Bag or Keg

Image Credit: Brett Johnson (C)
I do not have a 'canyon keg' in the picture above but basically the dry bag and keg serve the same purpose. - to keep its contents dry.
Before I took canyoneering seriously back in 1999, I used literally a large black garbage bag to keep my entire bag dry. Foolish me. It was just a matter of time before I got a puncture hole in the bag and my sandwich and everything else was all wet.
Thankfully now, many companies now make drybags. Most don't make them for canyoneering, but most any will do.
Drybags with the built-in valves are highly recommended as they incredible more versatile than one that doesn't have a valve.
How it works is that you put your contents inside the drybag, take the top of the drybag and fold a one-inch fold continually until you get a big pouch of air in the middle. This is where the valve comes in handy. Open the valve, purge the air out, and finally - the most important step - close the valve.
These drybags will ensure the contents as they are built with a durable plastic. They are not foolproof and can still rupture if used incorrectly or are punctured with a knife.
Check the Quick Facts page to see what types the community uses.
Headlamp

Image Credit: Brett Johnson (C)
A waterproof headlamp (and with extra batteries in your drybag...see why I listed the drybag first?).
It's only a matter of time (not if) when your canyon trip takes longer than you expected and will be hiking in the dark.
I use the Black Diamond - Storm. It's fully waterproof, uses 4 AAA batteries, over 350 lumens, has a spot and flood light, along with a green, blue and red LED. Blue isn't necessary, but the red is good as it doesn't hurt your night vision.
Water Container

Image Credit: Brett Johnson (C)
There is some debate in the canyoneering world of whether a reservoir (or bladder) system, such as the one I use in the picture (Camelbak 100 ounces (3 liters)) or whether Nalgene bottles are better. To answer quickly, I think it just all depends on what you like. Both have their pros and cons.
A bladder system has the drawback of being punctured if the backpack is dropped from a tall height, is not easy to know how much water is left without taking it out of the backpack, and when swimming through stagnant water the bite valve will go through that same water and may end up in your mouth, and lastly, if it is full of water before driving to the canyon and if the valve is laying against gear on the ride down, it's possible that some object could be pressed against it leaving the valve open the entire time wasting all of that water before you start your trip. Hopefully you have a backup!
A Nalgene bottle is very durable, will not suffer to punctures, but are large and do not keep water cold for too long. But they are easy to refill, can easily attach them to the outside of backpacks, and can share them easily amongst others. A Nalgene bottle from last I checked from my local REI store was $10. Not a bad price! If you prefer the Nalgene route, I would suggest bringing three.
Along with hydration, on longer day canyons, I will bring a water purifier. I have had those "you never know" moments come true! IE the approach to the canyon took longer than we anticipated so we had to filter pothole water. Surprisingly, the water tasted okay but I had clean, clear water to make it through the canyon. I would suggest the same, especially if you are doing backpacking canyoneering in places like Escalante and Zion.
Sun-screen

Image Credit: Brett Johnson (C)
This is an essential core item of Canyoneering. You will be hiking in a lot of hot places and where there is a lot of sun exposure. Protecting your face and skin are paramount in helping prevent against skin-cancer. You don't need to bring a big bottle like the I have pictured, but bring one that is travel-size, is the lotion type (and not the aerosol) and is a SPF that is 30 or above (according to the American Academy of Dermatology).
Re-apply throughout the day, especially when you are done with the canyon and are making the slog hike back to your car in direct sunlight.
If you don't like to wear sunscreen, I would suggest bring a hat or even a buff that you can wear to protect your face and neck.
LifeStraw®

Image Credit: Brett Johnson (C)
A LifeStraw® is a water-purifier that uses a hollow-membrane filter to clean contaminated water. From their website, it can: "remove bacteria, parasites and microplastics...weighs only two ounces...filters 1000 gallons (can last one individual drinking water for 5 years...no shelf life...[and is] easy to clean and store."
The reason why I think it is an essential canyoneering tool is because 1) it is very light (just two ounces), 2) you can leave in your canyoneering backpack and forget it but can know that you can purify pothole water if the need arrives, and 3) it may actually save your life or stave off dehydration in the hot-desert, and 4) it's only $20.
You may not use it for many months or even years, and that's okay. There is no shelf life on these things! But, that one time you are in the hot desert of Escalante and that approach to the canyon took longer than was expected and nearly ran out of your water, this could be your life-saver.
I usually keep mine in my accessory hood of my canyoneering backpack so it's out of the way. Also, when there is flowing water in a canyon, I will sometimes use this filter to drink the stream from and then save my bottled water for the hike out therefore prolonging my water capacity.
Not saying you absolutely need it, but for $20, it offers an inexpensive service in case of emergencies (especially when someone forgets to bring the hand-pump ceramic water purifier).
Map (& GPS)

Image Credit: Brett Johnson (C)
A printed map of the canyon(s) that you will be visiting is considered by most to be a must. Phone batteries don't last for forever, screens can crack, can be unforgiving when submerged in water, and do not handle falls from heights well.
While admittedly, I do use my phone (with an extra charger) for GPS coordinates for the approach hike and exit, I also carry a 12K and sometimes a 24K-topo detail map of the canyon(s) that I am doing. If it's a short canyon that I have done numerous times, I won't carry a map, but if it's one that I have never done, then yes.
I like the maps from National Geographic as they are printed on waterproof paper and are about $12 for a single USGS quad.
The USGS does provide online maps for free, but it will be up to you to print them out. You could laminate it or put it in your drybag for safe keeping.
In my early days of canyoneering, I use to laminate all of my canyon beta. I was worried about them getting wet in potholes or having the drybag being punctured or failing, etc. Looking back, I'm glad I did it but it was expensive.
If you look at the picture above you can see my Zion map unfolded a bit. I spent a few hours one night many, many years ago and marked in red the canyon names and paths for every canyon that I had beta for. That way, I had a "master map" and could reflect on it. After starting at it at campfires, I soon became very familiar with how Zion was laid out and where prominent features or canyons were. This really helped me to get my bearings and orientation laid out in my head.
If you can spare the time, I would suggest in doing the same so that you too can become an expert in those areas. That way if an emergency does happen, you will be more prepared, can give better directions, and can have a sense of mileage of where things are laid out. Being unprepared is one of the worst and scary feelings while canyoneering. And not knowing, is even worse.
It must also be said that more than one person should know the lay-out of the land too. It shouldn't rest on one person alone. If you can encourage more of your group to look at the maps and become familiarized, the better and more efficient your group will be. And that's what you want in canyoneering - a fine-tune efficient canyoneering group.
First-Aid Kit

Image Credit: Brett Johnson (C)
Extra Clothing & Light Jacket
Picture and text coming soon.