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REI Co-op Flash 55 Review

It may not be a heavy load hauler, but for moderate loads, this pack is comfortable and has a great set of features, all at an affordable price
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REI Co-op Flash 55 Review (The REI Flash 55 being tested on the Colorado Trail.)
The REI Flash 55 being tested on the Colorado Trail.
Credit: Sam Schild
Price:  $199 List
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Manufacturer:   REI
By Sam Schild and Adam Paashaus  ⋅  May 17, 2024
81
OVERALL
SCORE


RANKED
#4 of 16
  • Comfort - 40% 8.0
  • Ease of Use - 25% 8.0
  • Weight-to-Volume Ratio - 20% 9.0
  • Adjustability - 15% 7.0

Our Verdict

The REI Flash 55 is an all-around great value backpacking pack among an impressive backpack lineup. It carries a medium load well but is not intended for loads much over 30 pounds. Even with a ton of pockets and features, the pack is super lightweight due to thin fabrics and a lighter-duty suspension. The hip pockets, top lid, and shoulder strap pocket are all removable to save an additional seven ounces, and the side compression straps can be removed to better suit your needs for any trip. Those wanting a lightweight pack with a lot of versatility will love this option, and with its low price, we think this is a perfect pack for those looking to keep a trimmed-down pack load. If you're interested in how it ranks next to the competition, have a look at our best backpacking backpack review.
REASONS TO BUY
Light-weight
Comfortable
Easily personalized
Inexpensive
REASONS TO AVOID
Not the most durable
Low maximum load weight
Editor's Note: We updated this article on May 17, 2024, to verify our current testing and comparisons are still accurate to ensure we still stand behind our findings.

Compare to Similar Products

 
rei co-op flash 55
This Product
REI Co-op Flash 55
Awards Best Buy Award  Top Pick Award   
Price $199 List
$199.00 at REI
$194.89 at REICheck Price at Backcountry
Compare at 3 sellers
$187.46 at Backcountry$225.57 at Amazon
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Bottom Line The Flash 55 is a great value, with excellent features and a great weight to volume ratio at an affordable priceThis pack is super adjustable, has great pockets, and can comfortably carry a heavy loadAn affordable pack with lots of organizational features and three access points to the main compartmentThis is an excellent lightweight backpack that has solid suspension and a comfortable mesh back panelThis backpack is great for lightweight backpacking and is very comfortable
Rating Categories REI Co-op Flash 55 Gregory Paragon 58 Deuter Aircontact C... Gregory Focal 58 Osprey Exos 58
Comfort (40%)
8.0
8.0
8.0
8.0
8.0
Ease of Use (25%)
8.0
9.0
8.0
7.0
6.0
Weight-to-Volume Ratio (20%)
9.0
7.0
5.0
9.0
8.5
Adjustability (15%)
7.0
8.5
9.0
5.0
7.0
Specs REI Co-op Flash 55 Gregory Paragon 58 Deuter Aircontact C... Gregory Focal 58 Osprey Exos 58
Measured Weight 2.8 lb 3.6 lb 5.2 lb 2.7 lb 2.8 lb
Weight per Liter 0.81 oz/L 0.99 oz/L 1.11 oz/L 0.74 oz/L 0.77 oz/L
Advertised Volume 55 L 58 L 65 L + 10 L 58 L 58 L
Organization Compartments Lid, front mesh pockets, 2 side pockets per side, hip belt pockets, shoulder strap pocket Lid with interior and exterior zipper pockets, front mesh pocket, side water bottle pockets, hip belt pockets, sleeping bag compartment Lid with two zippered pockets, front mesh pocket, side water bottle pockets, hip belt pockets, sleeping bag compartment Lid, front mesh pocket, side water bottle pockets, hip belt pockets Lid with interior and exterior zipper pockets, front mesh pocket, side water bottle pockets, hip belt pockets
Access Top Top, side, bottom Top, front, bottom Top Top
Hydration Compatible Yes Yes Yes Yes Yes
Sleeping Bag Compartment No Yes Yes No No
Materials Main Body: 100D ripstop nylon
Bottom: 420D nylon
Main Body: 100D High Density Nylon / 210D High Density Nylon
Bottom: 420D High Density Nylon
Main: 235-denier polyamide
Bottom/high-wear areas: 500-denier textured polyamide
100% Nylon Recycled 100D high tenacity nylon ripstop, PFC/PFAS-free DWR
Measured Volume (main compartment) 45 L 50 L 52 L (not measured) 47 L

Our Analysis and Test Results

The REI Flash 55 is a cleverly designed pack, giving the user a way to personalize the feature set. This pack is a great option for a wide range of users. For being such a lightweight pack, we were surprised by how comfortably it carries a backpacking load.

Performance Comparison


rei co-op flash 55 - the flash 55 is a great fast and light pack for all types of...
The Flash 55 is a great fast and light pack for all types of adventures.
Credit: Sam Schild

Comfort


The Flash 55 is quite comfortable. We found this pack hugs your body well. As long as the load is under the 30-pound weight limit, we never complained about how this pack felt, even on our longest days on the trail. It feels solidly planted on your back, and the frame effectively disperses the load between the hip belt and shoulder straps.


Instead of having a hard plastic frame sheet and aluminum stays, the Flash 55 uses a spring steel perimeter style frame that feels as though it moves with you while supporting the pack's load comfortably. The 3D contoured back panel and waist belt have carefully positioned padding to keep the pack comfortable and supportive yet allow air to flow through gaps in the padding. The hip belt and shoulder straps also have this same dense foam padding. It feels solid but still provides enough cushion on your shoulders and hips. The foam used on the back panel, shoulder straps, and waist belt is also perforated. These small holes in the dense foam allow air to flow through. The perforated foam, combined with the 3D contoured back panel foam, keeps your back cool on long, hot hiking days.

rei co-op flash 55 - the foam back panel allows plenty of airflow onto our back, hips...
The foam back panel allows plenty of airflow onto our back, hips, and shoulders while still feeling solid.
Credit: Sam Schild

The shoulder straps, intended to support less weight than the hip belt, have slightly less-dense foam cushioning. They feature breathable mesh both against your body and on the outer face of the straps for maximum breathability.

rei co-op flash 55 - the shoulder straps are padded with perforated foam and have mesh on...
The shoulder straps are padded with perforated foam and have mesh on both sides of the straps for maximum ventilation.
Credit: Sam Schild

Ease of Use


REI's Packmod design utilized in the Flash 55 is excellent. It has a handful of clever features that can be removed or adapted to help make packing for any trip a breeze. The modular aspects of this backpacking backpack include two hip belt pockets (one mesh, one ripstop), a mesh shoulder strap pocket (seemingly made specifically for a smartphone), two side compression straps per side, a top lid, and a tool attachment loop.


We especially love that the lid on this pack can be removed in a way that doesn't feel like an afterthought. The main pack body is closed with a roll-top closure to help compress the load to the right size, keeping the contents stable underneath the lid. If you go without the lid, the buckles used to secure it can double as side roll-top closure buckles. Simply move the buckles intended to hold the lid down to the back of the pack to hold the roll-top closure down instead.

The top lid on the Flash 55 is very convenient to use, but it's...
The top lid on the Flash 55 is very convenient to use, but it's removable if you don't need the convenience and added weight.
The lid-closure straps double as roll-top closure straps if you...
The lid-closure straps double as roll-top closure straps if you remove the top lid from the Flash 55.
The top of the Flash with (left) and without (right) the brain attached.

The hip belt pockets on the Flash 55 are also very easy to use. Both pockets zip shut and are large enough to hold a smartphone or enough bars to keep you snacking all afternoon. They'll easily hold a map and compass, a headlamp, snacks, or any other small items you may want on the go. If you're trying to strip weight, these pockets can also be removed from the waistbelt altogether. One of the pockets uses a durable mesh, and the other is made with ripstop nylon.

We love the removable mesh shoulder strap pocket. This pocket is the perfect place for a phone so it can be ready when you need it. As it is made of mesh, it isn't waterproof, but if it does get wet, it won't stay that way for long. It has a velcro closure, so your phone won't fall out when you bend over. Here again, this pocket can be removed completely or switched from the right shoulder strap to the left. The side compression straps can easily be repositioned up or down the side of the pack to get the optimal positioning to secure any load. Following the theme of this customizable pack, if you don't want them at all, they can be removed.

rei co-op flash 55 - one hip belt pocket on the flash 55 is made with ripstop nylon, and...
One hip belt pocket on the Flash 55 is made with ripstop nylon, and the other is made with mesh, both pockets zip shut and are big enough for a smartphone and more.
Credit: Sam Schild

Everyone loves a good breathable, stretchy mesh front stash pocket, and the Flash 55 doesn't disappoint here. They go a step further by offering two more cavernous external ripstop pockets, one on each side between the side bottle pockets and the front mesh pocket. All these pockets are super handy for layers, lunch, a water filter, etc. The less we have to open the main compartment on a hike, the better, and these extra pockets allow for nearly unlimited packing options.

The Flash 55 is hydration compatible, but no pack is complete without a set of side bottle pockets, and these are some of the best-executed bottle pockets we've seen. They hold wide-mouth bottles with ease. And with the help of a strap that can be snapped partially across the opening, these pockets can secure narrow-mouth bottles without flopping around. To keep bottles easy to grab, many pack makers let you load the bottles in from the side. However, certain bottles put in this way can get in the way of your natural arm swing. The Flash 55 keeps bottles in the vertical orientation, but because they are positioned so far forward, they are still easy to grab for even those who may not have the most flexibility.

rei co-op flash 55 - the shoulder strap pocket is the perfect place to keep a smartphone...
The shoulder strap pocket is the perfect place to keep a smartphone ready to snap a picture or check GPS maps.
Credit: Sam Schild

The Flash 55 uses one main pack body rather than incorporating a separate sleeping bag compartment. There are also no straps on the bottom of the pack for stowing a closed-cell sleeping pad, but you could easily strap one under the brain on top if you want. With all the Packmod items and their versatility, the Flash 55 is one of the most feature-packed bags in our lineup.

rei co-op flash 55 - we love the multiple side pockets on the flash 55, which are big...
We love the multiple side pockets on the Flash 55, which are big enough to store 3 liters of water per side.
Credit: Sam Schild

Weight-to-Volume Ratio


We loved how lightweight the Flash 55 is. With the weight as low as it is, you'd think it wouldn't carry weight very well. But this backpack carries an average backpacking load better than packs nearly twice its weight.


This pack is extremely comfortable on long days when the sun gets low and camp can't come soon enough. The Flash is one of the lightest we tested at well under 3 pounds for 55 liters of packing space. If you remove the lid and many optional pockets and straps, it's even lighter.

rei co-op flash 55 - the flash can be stripped down to lower weight, while still offering...
The Flash can be stripped down to lower weight, while still offering plenty of room for whatever you need to bring.
Credit: Sam Schild

Adjustability


The newest version of the Flash features an easy way to adjust the torso length to be taller or shorter. This way, you can fine-tune the fit to make the pack more comfortable.



This pack comes in 4 sizes: small, medium, large, and large torso with a small hip belt. Each size has enough adjustability to ensure you get a good fit even if you are on the border between two sizes.

The newest version of the Flash 55 now has an easy-to-use torso adjustment feature to dial in the fit.
Credit: Sam Schild

The waist belt padding is fixed in place on this pack. While the webbing on a medium will allow for up to a 50-inch waist, the padding will only reach around so far, making the pack less comfortable for those on the larger end of the size range. Overall, assuming you get the right size, the fit on this pack for most people is excellent.

rei co-op flash 55 - the waist belt on the medium-sized flash 55 can be adjusted from 30...
The waist belt on the medium-sized Flash 55 can be adjusted from 30 to 50 inches.
Credit: Sam Schild

Should You Buy the REI Flash 55?


The Flash 55 offers great usability for a low cost, making it a high-value item. For those looking for a lightweight, comfortable, user-friendly, and reasonably priced pack, this one is worth a look. It may not be the most durable, but the lightweight ripstop fabric will last plenty long enough if you take care of it. At this price, this pack has a lot to offer.

What Other Backpacking Backpacks Should You Consider?


The Flash 55 is an incredibly light, comfortable, versatile, and low-priced backpacking backpack for those looking to keep things streamlined and lightweight. If you want a serious load hauler, check out the Osprey Aether 65. If you're looking for an even more streamlined, ultralight, and long-trail-tested backpacking pack, check out the thru-hiker favorite Ultralight Adventure Equipment Catalyst. If you're looking for a seriously comfortable pack with fewer pockets, check out the Granite Gear Blaze 60.

Sam Schild and Adam Paashaus