REI Co-op Flash 15 Hydration Vest
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To move fast and light on the trail, keep your center of gravity tight. The REI Co-op Flash 15 hydration vest holds 1.75 L of water snug to your core while keeping you well supplied for your day hike.
Shop similar products- Adjustable waist and sternum straps dial in the fit to keep your load tight and balanced
- Breathable, padded mesh back and mesh shoulder straps help you stay cool on the trail
- Included 1.75 L HydraPak Elite™ SL reservoir has Plug-n-Play quick-disconnect hose and high-flow Blaster™ bite valve that self-seals after each sip
- 4 stretch-mesh chest pockets hold quick-grab items; they're also bottle compatible for more hydration
- Zippered chest pocket fits most cell phones; 2 internal slip pockets and a key fob keep you organized
- Top lid with adjustable strap lets you stash more gear
- Locator device-compatible pocket at top of shoulder
- 4 removable Packmod bungees can be moved to any loop on the pack to keep your load tight or to attach extra gear like trekking poles
- 2 attached tool loops on bottom of pack can be tucked away when not needed
- REI Co-op brand is certified to The Climate Label; we actively fund efforts to reduce carbon emissions across our business and support climate projects around the world
- Contains materials that meet the bluesign® criteria
Imported.
View the REI Co-op Flash Product LineView all REI Co-op Hiking Hydration Backpacks| Best Use | Hiking |
|---|---|
| Gear Capacity (L) | 15 liters |
| Gear Capacity (cu. in.) | 915 cubic inches |
| Reservoir Compatible | Yes |
| Reservoir Included | Yes |
| Bottle(s) Included | None |
| Liquid Capacity (L) | 1.75 liters |
| Liquid Capacity (fl. oz.) | 50 fluid ounces |
| Number of Exterior Pockets | 8 + main compartment |
| Material(s) | Ripstop nylon (bluesign approved) |
| Bite Valve Shut-off Switch | Yes |
| BPA Free | Yes |
| Dimensions | 16 x 10 x 8 inches |
| Gender | Unisex |
| Sustainability | Contains materials that meet the bluesign® criteria From a Climate Label Certified brand |
Better gear is built together
From feedback to field testing, all of our gear is dialed-in by REI Co-op members. Their adventures informed every stitch and detail—making for better, longer-lasting gear.
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Very comfortable and practical
This hydration pack is pretty great! The adjustable straps on the side are perfect to make sure it stays snug and good to adjust with the amount of layers you wear. I wore this pack hiking and running. Huge bonus that the bladder is included, and the 1.5L capacity is good for a mid distance hike, or a long run. The straps are super comfortable, and the pack has a surprising amount of storage capacity. Layers/supplies in the main pocket, snacks, small water bottles, and/or a phone can fit in the front strap pockets, which have a bungee adjustment to make sure nothing falls out. While running, it took a moment to get used to as I don’t typically run with a pack on, but after a couple miles I almost forgot I was wearing it. The hydration bladder did seem to move around a little bit, but this could be solved with putting a layer in there to take up the empty space. I do wish there was a way to cinch the bag smaller if you’re not adding anything besides water, but there are only cinches on one side for trekking poles. All around, I’m looking forward to wearing this on long runs and many hikes! Disclaimer: I received this product for free in exchange for an honest review.
Floppy/roomy running pack
This pack is the crossover between running and load carrying that I've been searching for. It needs work. It's got space, but it's very floppy because I don't usually use it's full gear volume capacity. So I have to strap down all the loose fabric. To do this, I've sewn some personal modifications. Added straps outside and inside. With the floppiness factor, the accessory webbing and loop attachments are already fraying and wearing thin. They'll fall off soon and I'll have better success sewing my own hardpoint attachments into the seams of the pack. Simplest complaint is the metal hook and cinch closure on the top. Convenient, right? Well, the metal gets really hot when it's been under the sun. A plastic buckle would do the same thing, be more lightweight, and would not hurt my fingers upon handling. Thankyou REI for offering this product.
Great for multi pitch climbing
I bought this pack to use on multi pitch climbs and it works great for that. I switched out the water bladder it came with for a 3L, partly because I wanted more water capacity and partly because I don’t like the bite valve on the bladder that comes with it. I store that plus a jacket and a first aide kit in the back. But the reason I bought it is for the strap pockets. I can have all my snacks, my radio, my phone for photos and mountainproject, and my headlamp within easy reach while climbing. I never have to take off the pack while climbing and that feels like it lowers my risk of dropping anything. Easy access to snacks and water at all times means I stay more hydrated and energized. I use the bottle storage compartments on the side of the bag to carry my approach shoes if I’m walking off the top of the route. The bag sits high on my back so I can easily reach everything on my harness and it doesn’t block my chalk.
Minor Issues / Great Vest
What I didn't like: The hydration bladder has a piece of silicone or plastic inside the bladder itself that meant I couldn't really use my standard cleaning kit (a bit of plastic that holds the bladder open to dry) - it prevented it from being fully inserted. I contacted hydrapak to ask about it, because some of their bladders have something like this that actually separates... not this model though. The bladder says that it is reversible. Hydrapak wrote back that it is partially reversible. I was able to turn it inside out, but the material sort of gathers where the interior connector is; and I don't know if mold would get into those areas. I store these in the freezer once I use them, and only put water in them... but just a concern for me. The small pockets on the front of the vest were too little. My gu was really too long for those... maybe some salt tabs.... The keeper for the bladder tube is pretty much permanently on one side. I prefer the other side. It didn't bother me once I got going. You can run the tube out either way. Maybe you can swap the sternum straps and reverse it, I don't know how to do that. I prefer a magnetic keeper, and will probably add one to the sternum strap... this way I can have it on my preferred side. Plus it's easier to grab a drink with those. What I liked: The vest was surprisingly comfortable on, and did not chafe. (I was out in 10-15 degrees with heavy wind gusts and some rain, so I was wearing several layers and chafing would have probably been impossible.) I filled the hydration bladder for each run. It never bounced around, even after I drank a good bit of water. I was able to put my iPhone 6 SE with otter box case (roughly 3x6") in the zip up pocket (snug fit). It also fit fine in a large pocket on the front of the vest, without bouncing. I am 5'5", and weigh 135-140 lbs. Kind of pear shaped. The medium fit really well over a number of cold weather layers. I had to fully tighten the sternum straps and partially tighten the side straps in just a tee-shirt, but still had room to tighten more if needed. A 16oz water bottle / snacks easily fit in either of the main open front pockets, and there is plenty of room inside the back of the vest for gear, more snacks and / or a jacket. I am used to bladders that either clip or velcro to the vest. I didn't think much of the little clip in this vest till I used it. EASY to attach and held the vest firmly in place. Appreciate the key clip inside the pack. The water had a little plastic taste after a couple of rinses, the first run - but that rapidly dissipated. The bite valve was easy drawing, much easier than some. This vest was COMFORTABLE. A bit heavier than some I own, but it feels well made. It is likely to become my go-to hydration vest for cold weather runs. I'll probably stay more minimalist in hot weather runs. I really like this vest and and plan to let some of my running club teammates try it out.
Comfortable & Just Right for a Day's Outing
I received this product from REI in exchange for an honest review. In general, I carry my rain jacket, the 1.75L bladder, food for the day, and my first aid kit. It will hold more. The side pockets look small, but they'll each hold a 1L Nalgene - Awesome! Used the Flash 15 on a XC MTB ride. Carried some head gear for varying temps, jacket (when not wearing it), first aid kit, phone, wallet, snacks, and 1.75L water. It felt good on my back. The wide shoulder straps were comfortable. I usually have problems with backpacks' narrow shoulder straps pressing on my right collarbone, which I broke several years ago in a bike accident and had surgically repaired. I also liked the secure shoulder strap pockets where I carried my phone (convenient access for maps & pictures), wallet, and some snacks. Finally, I wore the Flash 15 for 3 days over the 116 mile southern section of the New Mexico Off Road Runner bikepacking route. I carried water, first aid kit, jacket, light shirt, and lunch. It was comfortable and let me have ready access to water, gear, and food.
Pockets Galore
I had started trail running and ultra running when the pandemic first hit. The gyms were closed, and my brother has been trying to convince me for years to run trails with his, so it was time to give in. The miles got longer, and being a water hot, I invested in my first pack; a UD vesta! I loved it, and tried a few more after, but realized how finicky packs were. They could change, maybe they would fit just a little bit wrong, or the pockets were just all in the wrong spots. I started doing longer runs, and with a dog as my companion, it felt like upgrading to a bigger pack was ideal. I was skeptical of this pack at first honestly, I mean all the big name packs were US, Nathan, or Osprey, but I was pleasantly surprised! (1) Pockets galore! 7 in the front, one big compartment in the back, and two side mesh pockets. Yes, many running vests have a lot of pockets, but these were all just conveniently places in all the right places. The front one fits my IPhone 10 perfectly. There is a zipper pocket for your keys! AND deep pockets for your soft flask! (2) The adjustability surprised me. For reference, I’m a XS/S for UD packs. I got this in a S/M and was really concerned that it wouldn’t fit me. Surprise, it does! The straps all cinch in just right, and I was surprised. No chafing so far. (3) The back panel is a foam piece that you can remove, which I appreciate. I don’t know if this was intended for this, but I’ve used it for lunch breaks when I wanted to sit on something soft due to a sore butt. Yup, it made a difference! (4) Bungee adjustable cords that cinch in the sides, uh yes! I’ve seen various designs on different packs but I love how these are removable. Very handy so far. Overall, this pack has worked really great for me. It’s been about three weeks, and I’m really enjoying it. Also, my dog loves the extra room for treat storage when I take her on runs with me.
It’s like the Swiss Army knife of hydration vest…
-Lightweight: light enough to be as least intrusive as possible for long 20 mile runs. -Size: yet big enough for a casual day hike if you need it to. Just big enough to pack some snacks, extra shirt, socks, etc. but not too big to where you have too much movement in the bag. -Material: quality materials through. Appears it will be pretty resistant to wear, yet still lightweight. Also like the fact that it’s not covered in obscene colors. Pockets: love the many pockets on the straps and sides. More than competitor versions, so that makes it more useful for me when I need it. The drawstrings are also a nice touch for keeping things tight when you’re running.
Square dudes, rejoice.
A lot of running packs are made for runner types, lithe elegant creatures. I am not elegant, more like the Slow rhino from Jumanji. Most packs are too small in the chest and constricting. This one has a nice open feel and fits well when you tighten the straps. Another nice thing about this pack is that it has a lot of ways to scrunch it down so if you don't fill up it's 15L capacity, you don't have to have stuff roll around. I do wish it had a lid instead of just a scrunch, but it works well none the less.
Little Bag for a Big Man
I bought this from the REI clearance area sans water bag. I used my existing Camelback 3L bag and hose and it worked well. I mostly like this bag especially for the purpose of trail running / hiking as it my case. I am a big guy at 6'3" 230 lbs, it looks a tad rediculous but is useful. My cheif complaint is that while it somewhat breaths as a backpack, the lack of any vertical ribs or padding on the back concentrates back sweat and saturates the bag - it sounds gross and in summer in Arizona is it. Relegated to keeping anything that i want 'dry' in the side or front pockets.
The miracle pack for hydration and day hikes
Love this hydration pack! It fits well and the fit is adjustable. Compared to a regular backpack, this eliminates the straps slipping off my shoulders or any bounce. I got this to carry water for orienteering, and now use it for everything. The pack holds a lot: my rain jacket and pants, food, first aid and head lamp, extra socks, a warm layer, and more. The pockets on the front are fantastics. My cell phone fits safely in the zip pockets, and i carry 2 soft flasks, along with snacks, sunscreen, mosquito net, bug spray, and keys in the others. I plan to bungee on my trekking poles.