REI Flash 55

The REI Flash 55 has a full frame with aluminum stays, J-shaped shoulder straps, a hipbelt, and load lifters - allowing it to carry over 22.7 kg (50 lb) comfortably. You will fill the pack before you reach its comfortable carry limit. The load lifters and frame effectively transfer weight to the hipbelt where the thick and stiff foam of the hipbelt carries the weight comfortably. When first trying on the Flash 55, the stiff foam may feel uncomfortable but it will conform to your body and feel more comfortable after hiking with it for an hour or so. The front pull hipbelt buckle makes it easy to tighten the hipbelt. The shoulder strap foam is a little softer and thinner than the hipbelt but still very comfortable. I prefer S-shaped shoulder straps because I find they fit a variety of body types better, but the J-shaped shoulder straps on the Flash 55 are relatively comfortable for the style and have a good length for the size medium pack I tested. The Flash 55 is a comfort-focused pack and one of the most comfortable packs I have tested.

Part of the reason the REI Flash 55 is so comfortable is the ability to have a really good fit. A pack could be designed to be very comfortable; but if it does not fit, then it will not feel comfortable. The Flash 55 is available in men’s and women’s versions with three sizes each and a fourth size that pairs a size large torso with a size small hipbelt for the men's packs and a size extra small torso and size medium hipbelt for the women’s packs. Each pack also features an adjustable torso; this combined with the variety of available sizes makes it possible for the majority of people to get the perfect fit and maximize the carrying comfort. The velcro mechanism for adjusting the torso is easy to use, durable, and maintains its placement. With the men’s and women’s sizes, REI advertised that the Flash 55 can accommodate torso length ranging from 38.1 cm (15 in) to 53.3 cm (21 in) and hip circumferences ranging from 76.2 cm (30 in) to 116.8 cm (46 in). The men’s size medium fits my 45.7 cm (18 in) torso well.

The REI Flash 55 has a 55 L main compartment that uses a roll top closure. I like roll top closures because the roll top can be extended to carry more gear or rolled down to compress the pack when it is not packed full. External pockets include two hipbelt pockets, side pockets, dedicated side water bottle pockets, a front pocket, a brain, and a shoulder pocket. The brain, hipbelt pockets, and shoulder pocket are all modular and can be removed. The hipbelt pockets are easy to use one handed and can fit a large phone. The front pocket is a combination of mesh and solid material that does not stretch. Because of the lack of stretch, the front pocket does not fit a lot of gear and can be difficult to use when the main compartment is full. The shoulder pocket is not my favorite design and I usually leave it at home.

Accessing water using the dedicated side pockets on the Flash 55 is one of the best features of any pack I have used. Even with short arms and bad shoulder flexibility, I can easily reach back and grab water bottles and put them back. The water bottle pockets have a button that can be used to make the pockets smaller or larger depending on the size of your water bottle. Having dedicated water bottle pockets allows for separate use of the side pockets for things like tent poles or chairs. The Flash 55 also has a water bladder sleeve in the main compartment and a port at the top middle of the pack.

Overall, the Flash 55 has excellent organizational ability and access to items when hiking is easy.

The main body of the REI Flash 55 is made with a 100 denier ripstop nylon and the bottom is made with a 210 denier ripstop nylon. Part of the front pocket and the water bottle pockets are a mesh. Overall construction of the pack is solid and I have not had any issues with seams coming apart or buckles breaking. The ripstop nylon pack materials are not very durable and will be cut by sharp objects and can develop tears or holes from abrasion. I have multiple holes in my pack from one 4-day desert trip where I was squeezing through some tight slot canyons and sliding down rocks. Other than that one trip though, I have not had any other issues with the pack.

Reviews on REI’s website are generally positive with a handful of negative reviews mentioning durability issues. So consider the conditions you backpack and maybe avoid the Flash 55 if you backpack in areas that are hard on gear. The Flash 55 comes with a one year return policy (for members) if you have any issues with the pack.

The main feature of the REI Flash 55 is the pair of water bottle pockets. Having easy access to water bottles on a backpacking pack is amazing for staying hydrated. The modularity of the Flash 55 is also great. The removable hipbelt pockets, shoulder pocket, and brain allows you to build the pack for your needs and can result in a pack that weighs closer to 1,000 g (2.2 lb) if all the modular items are removed. The side compression straps are also modular and the connection points can be moved to a variety of positions on the pack depending on your needs.

The REI Flash 55 weighs 1.28 kg (2.8 lb) on my scale, which is 29 g (1 oz) above the advertised weight. The pack body is made with lightweight material; so most of the pack weight is from the robust frame and foam. The weight reflects the comfort focus of the pack. The Flash 55 is not a lightweight pack.

The REI Flash 55 is a comfort focused pack. It weighs more than lightweight packs but is very comfortable and can carry a lot of weight comfortably. The Flash 55 is best for someone who wants a comfortable pack and may not have the opportunity to try a pack on before purchasing. The adjustable torso makes getting a good fit a lot more likely than with a pack that is not adjustable. If you have had troubles accessing water bottles on packs, then the Flash 55 will also solve that problem for you with the dedicated side water bottle pockets.