How to Choose Daypacks
Bend, Oregon
REI Co-op Flash 18 Pack
This product is not available. Good news: we have a newer version.
Handy in town, on trails and for short hikes away from basecamp, the Flash 18 pack cleverly converts into a stuff sack when you turn it inside out.
Shop newer version- Lightly padded stretch-mesh shoulder straps are breathable and comfy
- Back panel is lightly padded; pad slips out for use as a sit pad
- Hipbelt and sternum strap can be detached
- Sternum-strap buckle doubles as a safety whistle
- Hydration-compatible design includes a hose exit port and an internal sleeve for a reservoir (reservoir not included)
- Drawcord closure fully covers the top opening when cinched tight
- Pack exterior has a zippered pocket and daisy chain with ice axe loop
- 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
Our founders were mountaineers in search of a good ice axe. Tired of ordering from Switzerland, they started the Seattle co-op in 1938 to provide gear to their climber friends—by passing around a notebook. That sense of community is still central to the co-op today, where collective expertise from REI members and store employees informs the design of our products. This is gear built on purpose.
View 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 | 10 ounces |
| Fits Torso Length (in.) | 16 - 19 inches |
| Fits Waist/Hips | 26 - 42 inches |
| Material(s) | Ripstop nylon |
| Pack Access | Top |
| Number of Exterior Pockets | 1 main compartment |
| Reservoir Compatible | Yes |
| Dimensions | 16 x 9.5 x 8 inches |
| Gender | Unisex |
| Sustainability | From a Climate Label Certified brand |
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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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Most Helpful Favorable Review
277 people found this review helpful
7 years ago
Here's how fat this backpack can handle
I'm 6'0" (183 cm) tall and weigh 285 lbs (130 kg). My torso length is 21.5" (54.5 cm). I figured this pack would be small on me, but its weight, volume (capacity), and price are so good I couldn't resist giving it a try. The best info I could find was another reviewer saying it fit her "large" father (6'4", but only 190 lbs). So, I figured I'd share my experience with other, uh, "big-boned" people like me looking at this pack. You know, for science. Take a look at the photos. My shame is your gain!
This is a great pack, but it's not for me -- at least not for frequent use. I actually think the height (length) of the pack is impressive for an 18 L bag. And, to my amazement, the hip belt had room left over after going around my torso (a couple inches above my navel) where I'm 52 inches (132 cm) around. (I wasn't planning on using it, but, hey, The More You Know.) What sinks it for me is the fit of the shoulder straps on someone of my size. You can see from the photos that at its lowest position, the sternum strap sits just below my collarbones. My 50-inch (127 cm) chest is just too broad 'n' flabby for the straps to sit comfortably.
Again, the pack itself is great, and I highly recommend it for anyone with a body at least a few sizes smaller than mine.
Yes , I recommend this product
daniel_pa
PAMost Helpful Critical Review
19 people found this review helpful
8 years ago
Didn't even last 3 hours
Went for a quick run with a water bottle and jacket and a hole developed near the bottom seam.
doubled
Tustin, CA, United Statesdaniel_pa
Pennsylvania
Here's how fat this backpack can handle
7 years ago
I'm 6'0" (183 cm) tall and weigh 285 lbs (130 kg). My torso length is 21.5" (54.5 cm). I figured this pack would be small on me, but its weight, volume (capacity), and price are so good I couldn't resist giving it a try. The best info I could find was another reviewer saying it fit her "large" father (6'4", but only 190 lbs). So, I figured I'd share my experience with other, uh, "big-boned" people like me looking at this pack. You know, for science. Take a look at the photos. My shame is your gain! This is a great pack, but it's not for me -- at least not for frequent use. I actually think the height (length) of the pack is impressive for an 18 L bag. And, to my amazement, the hip belt had room left over after going around my torso (a couple inches above my navel) where I'm 52 inches (132 cm) around. (I wasn't planning on using it, but, hey, The More You Know.) What sinks it for me is the fit of the shoulder straps on someone of my size. You can see from the photos that at its lowest position, the sternum strap sits just below my collarbones. My 50-inch (127 cm) chest is just too broad 'n' flabby for the straps to sit comfortably. Again, the pack itself is great, and I highly recommend it for anyone with a body at least a few sizes smaller than mine.
Yes , I recommend this product
Travelaine
Dallas, TX
Can’t travel without it
6 years ago
I bought my Flashpack 5 years ago before a trekking trip to Machu Picchu, to use as a daypack on the Salkantay Trail. Since then it has been my trusted travel companion all over the world—most recently it made the entire Camino de Santiago with us last fall. It holds whatever you can stuff into it; it hasn’t come apart or lost any straps in the years I’ve had it; it goes into the washing machine and comes out ready for another adventure. Not meant to replace a true backpack, of course, and I wish my model had a water bottle sleeve on the outside, but it has been one of the best gear purchases I’ve made and I’d buy it again in a minute. Can’t beat the price for this little workhorse.
Yes , I recommend this product
JKAZU
SoCal
Great Value
9 years ago
Purchased mine 3 years ago for $25. I primarily use mine as a minimalist day pack for long rock climbing routes. It'll hold a 3L hydration bladder, approach shoes, jacket, food, with room left for assorted small items. It's small and light enough that you don't really notice it when climbing. Stuffed with clothing it also makes a comfortable camping pillow. It's surprisingly durable too. Negatives: The sternum strap comes off easily and I permanently lost mine years ago. Not comfortable carrying even moderately heavy loads, but that's not what this pack was designed for.
HylianMan
Fuquay Varina, NC, United States
Practically a Part of Me
8 years ago
I bought this pack six years ago, and I have used it nonstop since then. In fact, I liked it so much that I bought another one! This pack is perfect for grabbing my essentials and going about my day. I use it for sleepovers, conventions, concerts, day hikes, biking, college, and so on. I especially love that this pack is compatible with my water bladder. In addition to that, it works nicely on long backpacking trips as a stuff sack for my sleeping bag, dirty clothes, or whatever else I see fit. The durability is great. This pack has lasted me from my early days in the Boy Scouts all the way up to Eagle Scout and beyond. If you're looking for a great daypack that will last you a long time, look no further.
Yes , I recommend this product
climadeo
Bay Area, CA
Perfect for running commutes
9 years ago
I use this bag during my running commutes home from work. This is the second pack I've run with and by far my favorite. I love the waist clip, which stops me from getting swung around by the stuff I'm hauling. The bag is super light and the exterior pocket makes it easy to pull out my wallet to pop on the BART home. The interior pockets are great for stashing keys and an eye glass case and I've managed to fit my full change of clothes, shoes, denim jacket, book and water bottle in here! I can't recommend this bag enough! I just wish that there was a pocket for my phone on the shoulder straps, that would make it truly perfect.
rwedes
Great Companion Pack
9 years ago
Recently went on a 2 week European vacation, only took a larger backpack (opsprey farpoint 40) and this smaller back as a companion pack. It was my primary bag that I took out every day of the trip, it was always surprising how much this bag could fit (2 rain jackets, umbrella, hats, water bottles, etc. It is small and lightweight enough that I packed it inside my larger backpack during my initial flight and it didn't take up any extra space. The inside zipper pouch is a nice touch, felt better about placing cell phone in there out of the way of the rest of the bag. I would definitely recommend this bag to anyone looking for a 'day bag' or even a gym bag, as it is very small and compact, yet does a good job of swallowing your smaller gear and staying secure on your shoulders during a long days' walk
Yes , I recommend this product
AEES
Guam
My go-to for EVERYTHING
8 years ago
I've had mine for almost 10 years now, and it's the best $30 I ever spent. I mostly use it for day hiking and traveling. My favorite - and unheralded - feature is that it actually has daisy chain INSIDE the pack. This is perfect for traveling - you can tie your wallet/passport/camera to the inside so that you don't have to worry about some thief slashing it and collecting what falls out. Oh, it's also crazy durable. I've taken this hiking and caving countless times through sharp limestone karst and after 10 years, the only thing that caused any damage was my puppy who wanted the sandwich I had stashed inside.
Yes , I recommend this product
Ramy
France
Nice day pack, but made with bad fabrics
7 years ago
We buy one bag for each personnes of us for our trip. ( 3 personnes) We like it as it is light, for the dimensions, for the comfort as it is renforced in the back and for his inside pocket with a zip . The zip pocket is well placed because when you carry your backpack on your back, you can carry your day pack in the front and have easy acces to your keys or money in the zip pocket. The only backside is the bad fabric it is made with, very bad quality fabric. At the end of our trip the inside of the bag is peeling ! ....
No, I do not recommend this product
Dave
Richmond, VA, United States
Solid build, Okay quality
7 years ago
I have used this bag as a carry on, as a day pack, and currently use it to transport my gear to the climbing gym. It's a great size for me, and the opening of the bag does not lend itself easily to pick-pocketers while traveling, leaving me more at ease. There are some cons, though: the tab of fabric at the top to loosen the opening tore off due to improper threading(an easy fix), and the back tends to be hot in the summer time, but I have thrown this bag off cliffs, taken it swimming, and it's currently my go-to bag for anything I have to do during the day. Approaching my 1 yr anniversary with this bag, it shows no sign of stopping.
Yes , I recommend this product
Matt Boysen
Snohomish, WA, United States
Very Comfortable and Convenient
9 years ago
I bought this a couple weeks ago and have taken it out twice now. One pretty short hike with just a snack and sweatshirt, and on a relatively long day hike up granite peak with an extra shirt, snacks, and a 2.5 litre hydration bladder. Both times it was surprisingly comfortable and incredibly light. I look forward to packing this for day hikes in my backpacking gear too. I should also mention I'm bigger than most people, 6'3, 190 lbs, and this fits great. Pros: Incredibly comfortable, super light, packable, looks great (silver with yellow accents), works with large-ish hydration bladder. Cons: No shoulder strap clip for hydration bladder hose (easily fixable with some ingenuity)
Yes , I recommend this product
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