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REI Co-op Flash 18 Review

A simple pack that's easy on the wallet, ultralight, and super popular.
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Price:  $40 List | $39.95 at REI
Pros:  Affordable, minimalist design, lightweight, super packable.
Cons:  Few features, thin shoulder straps and hip belt.
Manufacturer:   REI
By Dan Scott ⋅ Review Editor  ⋅  May 13, 2019
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67
OVERALL
SCORE


RANKED
#5 of 16
  • Comfort - 25% 5
  • Weight - 25% 10
  • Versatility - 25% 6
  • Ease of Use - 15% 7
  • Durability - 10% 4

Our Verdict

We've owned a Flash 18 since the pack debuted in the late 2000s. We've used it in most environments under most weather conditions, ranging from day hikes to long, multi-pitch climbs and everything in between. Its low price, super low weight, and superb simplicity mean that we'll likely own a version of this pack for a very long time. This pack is a minimalist's dream and scored highly in weight and versatility. With a simple top-loading design opening into a single compartment, this pack remains comfortable during a myriad of activities. It's less hiking specific than any other we tested, but it can most certainly transition between activities. This is an especially good choice if you're on a budget and need a pack to take you from urban life to the mountain then to the crag. This pack climbs well due to its narrow profile and is an excellent option for multi-pitch days and summit attempts.


Compare to Similar Products

 
This Product
REI Co-op Flash 18
Awards  Editors' Choice Award Editors' Choice Award Top Pick Award Best Buy Award 
Price $39.95 at REI$139.00 at REI$109.95 at Backcountry
Compare at 3 sellers
$264.95 at Backcountry$54.95 at REI
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Star Rating
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Pros Affordable, minimalist design, lightweight, super packable.Comfortable, stabilizes heavy loads, thoughtful design, modular, recycled fabrics.Tons of features, fully adjustable, comfortable, well ventilated, separate hydration compartmentSubmersible, Durable, Comfortable, Duffel-zipper makes access easyLightweight, only the necessary features, comfortable suspension for the weight.
Cons Few features, thin shoulder straps and hip belt.Non-adjustable frame, only decent ventilation.Runs small, side mesh pockets are debatably smallHeavyUncomfortable with heavy loads, not durable.
Bottom Line A simple pack that's easy on the wallet, ultralight, and super popular.The most comfortable and stable daypack in our review also has just the right features for many outdoor adventures.This pack offers a time tested versatile design that is ready for any adventure.A pack that has managed the seemingly impossible: complete submergibility while still maintaining excellent ease of use.This pack is an excellent value, providing all-around performance for light and fast activities at a bargain price.
Rating Categories REI Co-op Flash 18 REI Co-op Traverse 35 Osprey Talon 22 Ortlieb Atrack 25 REI Co-op Flash 22
Comfort (25%)
10
0
5
10
0
10
10
0
9
10
0
10
10
0
6
Weight (25%)
10
0
10
10
0
7
10
0
7
10
0
4
10
0
9
Versatility (25%)
10
0
6
10
0
7
10
0
9
10
0
7
10
0
7
Ease Of Use (15%)
10
0
7
10
0
8
10
0
7
10
0
9
10
0
8
Durability (10%)
10
0
4
10
0
9
10
0
7
10
0
9
10
0
5
Specs REI Co-op Flash 18 REI Co-op Traverse... Osprey Talon 22 Ortlieb Atrack 25 REI Co-op Flash 22
Weight (ounces) 9.07 53.69 27.44 51.835 12.64
Measured volume (liters) 17.89 48.34 22.56 30.3 23.44
Back Construction Simple foam pad Spring steel Vented, contoured External wire frame Simple foam pad
Hydration Internal hydration sleeve Internal hydration sleeve Externally accessed sleeve, holds up to 3L, bladder not included no sleeve, but straps inside Internal hydration sleeve
Hipbelt 3/4" webbing removable 3D Contoured hip belt Broad, padded, with pockets broad, padded, textured 3/4" webbing removable
Number of pockets 2 9 9 9 5
Description of Pockets 1 main top loader, 1 outer zippered 1 main top loader, 1 outer flap with nylon/stretchy-mesh, 1 outer zippered, 1 top lid zippered, 1 top lid mesh, 2 side stretchy mesh, 2 hip belt 1 main compartment zippered, 1 stretchy mesh shoulder strap, 2 waist zippered, 2 side stretchy mesh, 1 back stretchy mesh, 1 top zippered, 1 open hydration reservoir pocket behind back panel 1 main duffel-style TIZIP zipper, 2 small internal zippered organizational pockets, 2 large zippered organizational pockets, 2 side stretchy mesh, 2 hipbelt zippered stretchy mesh 1 main top loader, 2 side stretchy mesh, 1 top lid zippered, 1 outer zippered
Materials Nylon Recycled 200D ripstop nylon, recycled 400D Oxford packcloth Nylon PVC-free waterproof nylon Nylon
Outside Carry Options 1 exterior daisy chain Ice axe loop and bungee holder, 12 attachment loops along bottom and sides of pack Bungee helmet tab, Blinker light patch, ice axe loop and bungee holder, front-side pole carry bungee loops modular strap attachment system: 4 side compression straps included, top and bottom vertical straps, optional helmet carrier and extra modular straps Ice axe loop and bungee holder, daisy chains, attachment loops around back panel
Whistle Yes Yes Yes No Yes
Key Clip Yes Yes Yes Yes Yes
Notable other Features Removeable foam back panel doubles as sit pad, removeable sternum and hip belt straps Uplift compression straps really tighten down the load Blinker patch, front-side pole carry loops waterproof and submersible, fully adjustable frame, duffel style opening for easy access Removeable foam back panel doubles as sit pad, removeable sternum and hip belt straps, attachment loops to add compression cords
Weight : Volume (oz/L) 0.51 1.11 1.22 1.71 0.54
Weight : Volume Ranking 1 9 13 17 2

Our Analysis and Test Results

The Updated Flash 18


The shape of the Flash 18 was tweaked slightly in the hopes of making loading and access even easier, and the entire bag is now an ounce lighter (9 oz instead of the previous 10 oz). It is also available in some new colors this season. See the updated Flash 18 in the left image, below, which we tested this year.

REI Flash 18

This award winner still retails for the same great budget price of $40. We put it through our usual rigorous testing to compare it to this year's other daypack contenders.

Performance Comparison


Check out the REI Flash 18 for one of the most versatile packs we tested, at a price you can't refuse. It carries light loads securely, is easy to stuff and dump out quickly, and can easily find its way on all but the most gear-intensive adventures.

The Flash is the daypack of choice for this Great Dane.
The Flash is the daypack of choice for this Great Dane.

Comfort


This pack sits comfortably on your back as long as you don't overstuff it. Due to the frameless back panel, it is easy to overload, causing the back paneling to round. The shoulder straps are thin and breathable but are the first source of discomfort when weighing this pack down with anything over 10-15 pounds. Unlike the Flash 22, the shoulder straps are not padded, which turns out to make a big difference in comfort. This is an essentials-only type of pack. If you want a pack to carry more gear more comfortably, try our Editors' Choice winner, the Osprey Talon 22.

The flash fits most people  from our lead tester (pictured here; 6'5"  225 lbs)  to his smaller partner (5'5"  110 lbs).
The Flash 18 is one-size-fits most  and it really does. It fit both this 5'5"  110 lbs tester  and our lead tester  who is 6'5"  225 lbs.

The Flash is a one-size-fits-most pack, but we found that across a range of torso sizes, from a 5'5" tester to a 6'5" tester, we could cinch the suspension down tight on the shoulders for bouncy trail running, or let some out and get the weight at least partly on the hips for hiking. When cinched down, it didn't bounce and hugged the torso well, making it ideal for long runs.

Hikers who prefer a little more access and a bit more comfort should look at the Osprey Daylite or Deuter Speed Lite. Both of these packs have more features, a front-loading design, are more accessible to external pockets and have more comfortable straps.

One useful tip is that you can remove the light padding in the back of the back and use it as a cushion on your lunch break. If you happen to be looking for a little more structure in the back paneling, you can easily replace this foam with a stiffer version. Even a Sam Splint works great (and then you're doubly prepared). This approach also works well with the Virga 26.

Weight-to-Volume Ratio


You can't beat the low weight and low price of this bag. Weighing just nine ounces, it is a great little guy to have in your arsenal, even if you never use it for an actual day hike. It is the lightest pack we reviewed. If going ultra-lightweight is your thing, be sure to look at the Granite Gear Virga 26, which is a bigger version of the Flash 18. Both packs are essentially just tubes with straps. The Virga, however, feels much bigger than the Flash and would work for quick overnight ultralight trips if needed.

Ultralight packs are great for light loads  but don't offer much ventilation or stability.
Ultralight packs are great for light loads, but don't offer much ventilation or stability.

Versatility


Due to the lightweight, minimalist design, this pack has versatility beyond a typical daypack. One of our testers ran the Grand Canyon from rim-to-rim and back with a version of this pack and found that it worked well.

The Flash 18 also works great for bike commuting or climbing and packs down to about the size of a softball. This small size makes it easy to bring on longer backpacking trips or travels as a separate daypack. In this scenario, it can be used as a stuff sack inside a larger pack, and then removed to use as a summit pack when needed. If you don't plan on using it this way, then perhaps you should consider if this feature is worth the loss of comfort and ease of use. Other packs like the Osprey Daylite and Deuter Speed Lite are near as light as the Flash but offer better features, comfort, and ease of use.

The top loading design lets you accommodate bulky items that can be hard to pack into panel loading designs.
The top loading design lets you accommodate bulky items that can be hard to pack into panel loading designs.

Ease of Use


The Flash 18 is a relatively simple pack but has what you need for many different adventures. It is hydration compatible and also comes with an external pocket including a key clip for stowing smaller items. It has a daisy chain fixed to the outside for extra external carry options, such as clipping your shoes on. There are four perimeter loops next to the back panel that you can clip things to, or use to secure cordage for extra lashing options. The base of the daisy chain has a loop for an ice axe, and you can connect the top with a ski strap or Velcro loop. However, if climbing is your thing, you should take a close look at the Arc'teryx Cierzo 18.

This pack is simple: just one zippered outer pocket plus the main compartment. However  it gets the job done.
This pack is simple: just one zippered outer pocket plus the main compartment. However, it gets the job done.

The waist belt offers some stability, but the thin webbing becomes uncomfortable with heavier loads. The sternum strap does come equipped with a whistle. However, on larger torsos, it does not lower enough on the shoulder straps for a proper fit and can make you feel as though you're being choked. The good news is that both of these features are detachable. Unlike past versions of this pack, this model has nylon carry loop at the top. This makes it slightly easier to clip into the anchor if used for multi-pitch rock climbing.

The side opening front pocket was a really convenient place to store items while traveling. Just be sure to watch your back!
As you can see  the main compartment now features two small stuff pockets sized perfectly for a phone or keys.

A 14-inch laptop will fit into this pack. However, the bag does not provide much protection for any device, other than a thin foam pad. While it is hydration compatible, a three-liter bladder takes up most of the space in the small bag. If you are looking for useful features, check out our Editors' Choice Osprey Talon 22.

Durability


This year's Flash 18 performed surprisingly well in our hose test. The fabric shed water well, but of course let in drips through the cinch top. The cinch flap kept contents dry for a little while, but we think of this pack as being more ideal for drying quickly than keeping things dry.

We also lightly tested how much snow can work its way in through the gap created with the drawstring. During our test, the pack remained snow free, but more rigorous activity in a harsh storm would almost certainly allow snow and ice to come through.

Whether an avid hiker  or just playing around in the mountains  the Flash 18 is ready for anything.
Whether an avid hiker, or just playing around in the mountains, the Flash 18 is ready for anything.

Through months of testing, including bushwhacking through dense foliage in Red Rocks National Conservation Area, the pack survived without noticeable wear. On a side note, however, one tester hauled an older version of this model up 90 feet on the Diamond of Long's Peak. It scraped its way up, snagging along the way, and eventually arrived at the belay battered and torn, but was still usable. For what it's worth, that version and the newest version seem to be made of the same material. The Flash packs are also remarkably easy to repair, having very simple construction. Just clean it up, slap on some tape, and it's good to go.

Best Application


This bag's options are pretty endless when you consider weight, price, and versatility. It's perfect for day hikes, grocery shopping, a school and gym bag, multi-pitch rock or ice climbing, and we love using it as a stuff sack inside larger packs (and then using it during summit bids). With all the various colors and patterns, you can find one of these for any style.

Value


The Flash 18 is the least expensive of the packs reviewed, but also the least durable for rigorous backcountry conditions. We find that it provides the excellent value for the dollar. Not only is this pack super versatile and lightweight, but it is also backed by the REI 100% satisfaction guarantee.

Conclusion


For the weight and price, this specialized and compact pack deserves your attention. The super simple design is ultralight and very inexpensive. Other packs are more durable and supportive of heavy loads, but for smaller missions and for tucking into the corner of your bigger bag, the Flash 18 is unique.


Dan Scott