How to Choose Daypacks
Bend, Oregon
REI Co-op Flash 18 Pack
This product is not available. Good news: we have a newer version.
So light it's barely there, the REI Co-op Flash 18 pack is nevertheless hydration compatible and big enough to hold the 10 essentials (and then some) for a day hike or ramble away from base camp.
Shop newer version- Now made with all bluesign®-approved materials, this product earns the bluesign® product designation
- For use in your larger backpack or duffel, the Flash 18 converts into a stuff sack simply by turning it inside out
- Breathable, stretch-mesh shoulder straps have fold-over padding that softens contact with your neck and shoulders
- Back panel is lightly padded; pad slips out for use as a sit pad
- Hipbelt and sternum strap can be detached to save weight
- Updated pack shape makes loading and access easier
- Hydration-compatible design includes a hose exit port and an internal sleeve for a reservoir (reservoir not included)
- Single-handed, quick-pull drawcord with small weather flap seals top
- Pack exterior has a zippered pocket and daisy chain with ice-axe loop
- Exterior loops can be used to lash on extra gear, add compression or tie the Flash 18 to a larger pack
- Made to reflect our love for people and the planet through the use of bluesign®-approved materials
- bluesign®-approved materials conserve resources and protect the health of the environment, workers and wearer (you!)
- 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
- Product meets the bluesign criteria
Imported.
View the REI Co-op Flash Product LineView all REI Co-op Daypacks| Best Use | Hiking |
|---|---|
| Bag Style | Backpack |
| Frame Type | Frameless |
| Ultralight | Yes |
| Gear Capacity (L) | 18 liters |
| Gear Capacity (cu. in.) | 1,100 cubic inches |
| Weight | 9 ounces |
| Fits Torso Length (in.) | 16-20 inches |
| Fits Waist/Hips | 26-42 inches |
| Material(s) | Ripstop nylon |
| Pack Access | Top |
| Number of Exterior Pockets | 1 + main compartment |
| Hipbelt | Yes |
| Reservoir Compatible | Yes |
| Dimensions | 17 x 10 x 7 inches |
| Gender | Unisex |
| Sustainability | Product meets the bluesign® criteria From a Climate Label Certified brand |
Buying Advice
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Most Helpful Favorable Review
Great little pack, new version with bonus features
goodmojo3 years ago
I have had a few versions of this pack, beginning with the OG Flash UL that was basically a stuff sack with very minimal shoulder straps. This newest version (2021) is much more substantial, with the addition of a hipbelt, sternum strap, and an exterior zip pocket. But a somewhat unadvertised feature is the addition of little loops on top and bottom of the backpanel. These work well with some of the toggle-style bladder suspenders in certain backpacks, such as Gregory Maven, Deva, Baltoro, and others, enabling this pack to be used as a bladder sleeve inside of a larger backpack, and then once at camp, it can be easily removed for a summit pack, dayhiker, hauling water, collecting mushrooms, carrying camera gear- anything you need a small pack for while out in the woods. The addition of a thin foam backpanel on this version is a pro and a con- older versions with no padding were much more suited to being used as a stuff sack for clothes or a sleeping bag by simply turning it inside out. The padding on the newer version makes that type of use more cumbersome, but adds suspension and a more comfortable carrying capacity, and you can easily remove it for a minimalist sit pad. The price has doubled since the Flash UL, but so have the features, making this much better as a very usable and still lightweight daypack. Kudos to REI designers for improving on old styles, even though I still use my original Flash UL's all the time, the original "stuff sack with shoulder straps."
goodmojo
Olympia WA
11 people found this review helpful
Most Helpful Critical Review
Rubber like inner lining started peeling off.
Bob_Loblaw4 years ago
I purchased this awhile back (around 2013 -2014 or so) and used it on a couple of occasions. It was good for what I needed it for (packing wallet, phone, change of shirt, light windbreaker, snacks, water bottle, etc). I stored it away in my closet and forgot about it. Recently pulled it out from my closet and I noticed a sticky rubbery powdery stuff inside. I turned the inside out and noticed that the rubberlike lining (that I think makes it water proof somewhat) of the bag started peeling off. It made the inside a sticky mess and unusable. I didn't expect this bag to deteriorate like that being stored in my bedroom closet with AC on in the house. $40 wasted for a bag I've used on a couple of occasions.
Bob_Loblaw
11 people found this review helpful
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Aran
San Diego
Perfect for near death experiences
3 years ago
This was recommended for the REI Joshua Tree backpacking trip to be used during the scramble day. This was super light weight to stash in my large backpack and useful when hauling water to and from the cache. It was also great to have something so light on my back when scrambling over gigantic granite boulders, where one wrong move could send you to your death. So needless to say, I have totally bonded with this backpack as I came back alive. My son also used it for city exploring today and was perfect for him as well.
Age:35–44
Weight:150–175 lbs.
Height:5'8"
Yes , I recommend this product
Dave
Los Angeles
Great for multi-pitch climbing.
4 years ago
I really dislike climbing with a pack, but I also dislike clipping approach shoes to my harness and hiking down in climbing shoes. Thought I would give this a try and I am now converted. Have used it on several multi-pitch climbs and I barely notice it's there. Zipper pocket on the outside for small stuff is nice to have. And one of biggest assets is that this packs up so small that it fits in your main pack without taking up valuable space.
Age:55–64
Weight:150–175 lbs.
Height:5'11"
Yes , I recommend this product
Victor13
Woodbridge,VA
lightweight, water-resistant, versatile
4 years ago
Ok, so I've had this bag for 2 years now. I originally bought it on sale, as a quick bag to pack my camera and tripod for trips. This bag has survived quite a bit, but my most recent trip really put it on the test. I was coming back from a beach in Colombia on a mini boat over rough seas, this bag protected my unprotected camera and didn't let a single drop of water get in and damage my gear. At this point I might have packed myself in the bag lol. needless to say, this is an extremely versatile day pack, and an ultimate addition to your arsenal of gear.
Age:25–34
Weight:175–200 lbs.
Height:5'10"
Yes , I recommend this product
Michigan Day Hiker
Michigan
lightweight pack ideal for day-hiking with bladder
4 years ago
I pack pretty light and I do like to use a water bladder on longer day hikes. This pack combines the two perfectly! It's very lightweight but still pretty comfortable despite being frameless with minimal padding. The straps can help to distribute some of the weight but I wouldn't rely on it. I've carried ~10lb in this bag and it was ok, but seemed to me to be the upper limit of comfort before it really started to dig into the shoulders. The pack can fit my Osprey 3L water bladder but it requires some shimmying if it's completely full. If you only fill 2L, the bladder slips in the pocket easily.
Age:35–44
Weight:125–150 lbs.
Height:5'6"
Yes , I recommend this product
Bob_Loblaw
Rubber like inner lining started peeling off.
4 years ago
I purchased this awhile back (around 2013 -2014 or so) and used it on a couple of occasions. It was good for what I needed it for (packing wallet, phone, change of shirt, light windbreaker, snacks, water bottle, etc). I stored it away in my closet and forgot about it. Recently pulled it out from my closet and I noticed a sticky rubbery powdery stuff inside. I turned the inside out and noticed that the rubberlike lining (that I think makes it water proof somewhat) of the bag started peeling off. It made the inside a sticky mess and unusable. I didn't expect this bag to deteriorate like that being stored in my bedroom closet with AC on in the house. $40 wasted for a bag I've used on a couple of occasions.
Age:35–44
No, I do not recommend this product
Jane
Pennsylvania
My go to pack
4 years ago
I've had the flash pack for 5yrs now. I have a couple of other packs in my gear arsenal but this is the one I always grab. It's so lightweight, the bladder is real easy to install and remove, the straps don't cut into my shoulders, and it's extremely versatile. I use it the most for hiking and MTB, but I've also used this pack for travel, camping, and kayaking. I will definitely be purchasing another as back up for the day that I finally destroy this thing.
Age:35–44
Weight:125–150 lbs.
Height:5'3"
Yes , I recommend this product
goodmojo
Olympia WA
Great little pack, new version with bonus features
3 years ago
I have had a few versions of this pack, beginning with the OG Flash UL that was basically a stuff sack with very minimal shoulder straps. This newest version (2021) is much more substantial, with the addition of a hipbelt, sternum strap, and an exterior zip pocket. But a somewhat unadvertised feature is the addition of little loops on top and bottom of the backpanel. These work well with some of the toggle-style bladder suspenders in certain backpacks, such as Gregory Maven, Deva, Baltoro, and others, enabling this pack to be used as a bladder sleeve inside of a larger backpack, and then once at camp, it can be easily removed for a summit pack, dayhiker, hauling water, collecting mushrooms, carrying camera gear- anything you need a small pack for while out in the woods. The addition of a thin foam backpanel on this version is a pro and a con- older versions with no padding were much more suited to being used as a stuff sack for clothes or a sleeping bag by simply turning it inside out. The padding on the newer version makes that type of use more cumbersome, but adds suspension and a more comfortable carrying capacity, and you can easily remove it for a minimalist sit pad. The price has doubled since the Flash UL, but so have the features, making this much better as a very usable and still lightweight daypack. Kudos to REI designers for improving on old styles, even though I still use my original Flash UL's all the time, the original "stuff sack with shoulder straps."
Age:45–54
Weight:175–200 lbs.
Height:5'7"
Yes , I recommend this product
jcburtt
Massachuetts
Awesome UL pack
3 years ago
Bought this figuring I would use it as a summit pack when basecamping. Would appear to work great for that as you can easily flip it inside out to double as a stuff sack and is only 8oz. Turns out, it’s also just a great daypack on it’s own for traveling fast and light. Took it on a winter hike recently and fit my 3L Osprey bladder, extra layers, puffy jacket, food, and emergency/first aid kit. For me, that’s the most I would ever take on a day hike. Attached some shock cord to the outside to strap on snowshoes for the beginning of my hike when only microspikes were needed. Carried the weight (probably about 10-12lbs) comfortably and without issue. Can’t wait to try it out with an even lighter load in the summer. Amazing bang for the buck.
Age:35–44
Weight:200–225 lbs.
Yes , I recommend this product
NatashaRenee
San Antonio, TX
Not a bad option for kids/teens
4 years ago
Was looking for a good day pack for my daughter to get her used to using a hydration pack. This pack is really light weight and we love the color. It was a little confusing to figure out 1. how to weave the hydration tube through and 2. how to close it. It has a cinch close and the drawstring is pretty difficult to pull open and cinch closed. Hoping that will ease up with time/use. All in all this was a great intro pack.
Age:18–24
Weight:150–175 lbs.
Height:5'2"
Yes , I recommend this product
RConnole
Portland, OR
Day tripper while backpacking
3 years ago
I never thought I would use this until I went backpacking and just wanted a lightweight day hike pack that could be used as a compression in my back pack or clip outside. This does either/or and you won't notice the weight. If you are larger in size (I'm 6' and 190) the arm straps are a little tough getting in and out but its really not so bad and the lack of material keeps stowing it easy.
Age:35–44
Weight:175–200 lbs.
Height:6'0"
Yes , I recommend this product
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