Affordable, high-performing backpacks are few and far between. On our never-ending quest to locate and share with our readers the best kit available on the market, we’ve found plenty of models that tick either one box or the other, but rarely both. When REI’s most recent iteration of the popular Flash 45 Backpack popped onto the market last year, we were intrigued — what had the guys and gals at REI been up to since the last version of this popular pack first hit the shelves? And would this new, updated model finally deliver on both the price and performance fronts?
In this review, we aim to deliver our findings, starting off with a few insights that we hope will facilitate the selection process when choosing the ideal backpack for your adventures, and then moving onto an in-depth review of REI Co-Op’s Flash 45 to see how it measures up against these benchmark criteria for badass backpacks.
The capacity you require in a backpack will depend on what you plan on getting up to while out in the outdoors. Are you mainly a day-hiker? A day-hiker who throws in the odd overnighter? A thru-trekker or multi-day adventurer? Are you an everything-but-the-kitchen-sink kind of backpacker or an ultralight, gram-counting minimalist?
Answering the above questions and knowing your own, personal MO when hiking (lightweight wanderer or carefree-carrier-of-the-whole-kit-and-caboodle come what may) will narrow down the capacity range you need to be buying in.
Most backpack manufacturers list their pack’s capacity in liters (i.e. ‘40L.’, ‘55L’, ‘80L,’ etc.). To give you a very broad idea of how suitable these capacities might be for various trip durations, the following list offers a ballpark overview:
Ballpark Backpack Capacity Required*
* These figures will vary, naturally, depending on the season you’re hiking in (winter gear is bulkier and heavier) and the type of gear you have (ultralight and highly packable or old school and less so).
In addition to overall interior capacity, a few other considerations relating to storage determine a backpack’s suitability for your needs, most notably:
As with most outdoor gear items, a backpack’s weight or lack of weight compared to its competitors usually has a direct bearing on several other factors, in this case, storage capacity, durability, and ruggedness.
For most savvy buyers, one of the most important factors weight-wise when buying a new backpack is finding a pack that boasts a favorable weight-to-volume ratio.
2 lbs 10 oz
3 lbs 8 oz
The above table shows just how greatly pack weights can vary even within a limited range of storage capacities. It doesn’t, however, tell the whole story…The two ultralight models in this chart, the Kelty Redwing 44 and Patagonia Ascensionist, both use very thin and less durable fabrics, while the Black Diamond Mission 45 and Deuter Air Contact 45 +10 use incredibly hard-wearing materials that are designed to deal with a lot more rough treatment out on the trail.
The bottom line? When you get down to making your pre-purchase shortlist of potential packs, be sure to check what compromises are made in order to achieve any weight savings before heading to the checkout.
The materials used in your backpack will determine just how rugged and durable the pack will be. Material thickness is measured in “denier”, which is usually abbreviated to a simple “d” in product specs. Put simply, the higher the denier count the tougher the fabric. From the above list, the ultralight Patagonia Ascensionist uses 210d Cordura ripstop nylon, which (and the author can, sadly, speak from experience), is not the most rugged fabric out there and not built to withstand too many confrontations with rock, branches, or sharp objects inside your pack like crampons or (sadly), even plastic sporks. At the other end of the scale, the BD Mission uses super burly 420d ripstop nylon, which we’ve seen hauled up a cliff on the end of a rope on a multi-pitch climbing route (on spiky granite, no less) and come off no worse for wear.
A quick glance at the specs of the two aforementioned packs is revealing as regards the trade-off for tougher materials — while the Ascensionist weighs in at an incredibly friendly 2 lbs 0.5 oz, the Black Diamond Mission tips the scales at a ponderous 3 lbs 8 oz.
So how do you choose between the two? Well, knowing where you’re likely to be headed, what sort of terrain you’ll be traveling in, and how clumsy or indelicate you tend to be with your gear (!) will go a long way towards helping you make the decision. If you are likely to be strolling along wide, well-maintained trails in fairly open terrain then you can afford to go light on the denier count. If, however, you envision trekking through the dense forest, narrow slot canyons, scrambling, taking on the odd via ferrata or two, or simply know that a sturdier material would give you more peace of mind, then shooting for a pack with 300d+ fabric is likely to be the best choice for you.
Although we touched on storage and compartmentalization briefly above, it’s worth reiterating that it’s easier to make your pack fit your gear than vice-versa — it would, of course, be a bit of a shame to spend a wad of your hard-earned $ on a new pack only to then discover your tent, tent poles, or sleeping bag don’t fit inside the main compartment. The solution to this potential problems is simple: before buying, get out your measuring tape and take the measurements of all large gear items so you can check the measurements off against those given in your prospective backpack’s product description.
Another point of note with regard to storage is that the compartments of your backpack can be viewed as something akin to an email inbox, with separate ‘folders’ (in this case the pockets and compartments) in which you can store any gear you would prefer to keep separate. This can be useful for two reasons: first up, you can locate your gear more easily and keep certain items you’re likely to use frequently (or on and off) close to hand (map, windbreaker, water bottle); secondly, wet, sharp, or smelly gear items can be safely separated from dry, fragile, or clean items.
A backpack that doesn’t score high in the comfort stakes is, essentially, not one worth having. Your backpack comes second only perhaps to your shoes or boots in its potential to be the cause of serious discomfort while out on the trail. As such, ticking this box with room to spare should be one of your top priorities. Gauging comfort isn’t easy if buying online, but, in addition to user reviews, a few factors which will allow you to make an informed decision on a pack’s comfort levels include the following:
Measuring your back/torso length when fitting a backpack is done as follows:
Now that we’re all clued up on the ins and outs of a backpack and its main features, let’s see how the Rei Co-Op Flash 45 performs in each of the categories highlighted above.
At 45 liters, the Flash 45 straddles the ground between a very large day pack and backpacking pack suitable for 2 or 3 nights on the trail. This kind of versatility might appeal to buyers who don’t see themselves doing any long-distance thru-hiking and want one pack that’s suitable for every outing they’re likely to be making, from a short day hike to an (at a squeeze) 3 or 4-nighter.
Weighing in at 2 lbs and 12oz, the Flash 45 is a little heavier than most other packs in its performance range that have a similar capacity. All told, the weight-to-volume ratio in this pack is fairly poor and a definite drawback compared to more expensive models, but, given the Flash 45’s palatable price, those added few ounces may be easily overlooked for those working on a tighter budget.
The Flash 45 uses very tough, durable, 420d ripstop nylon materials in the main body of the pack, making it equal or superior to most of its competitors. On the downside, the mesh panels and pockets on the exterior of the pack are a touch on the flimsy side and it’s not hard to envision a stray branch or sharp gear item poking or ripping right through the material should the user not exercise a great deal of care.
All of the Flash’s 45-liter capacity is comprised in a single, large central well that measures 13 x 26 x 9 inches. One more endearing aspect about this pack’s design, however, is that the removable top lid allows you to customize the pack’s volume and either tighten and secure the load when traveling with less gear or squeeze in a few extra items when on longer trips. On the exterior of the pack, a duo of belt-strap pockets, two water-bottle pockets, a shoulder-strap pocket, and one large mesh pocket on the front of the pack offer plenty of additional storage points for gear items you don’t need to keep inside the pack.
Unlike many budget models of a backpack, the Flash 45 packs a very healthy number of appealing features. The most notable of these include:
We’re gonna avoid any beating about the bush here and call a spade a spade: the REI Flash 45 is a budget-priced pack that offers budget-priced performance. While there are certain endearing aspects to this pack — most notably the adjustable torso length, the wealth of exterior storage options, and the handy placement of the water bottle pockets — there are too many downsides and bugs in the pack’s design and overall performance for us to recommend it to anyone prioritizing performance over price.
If you’re looking to buy cheap, then yes, it’s hard to do a great deal better than the Flash 45, but by throwing just an extra $50 or so into your kitty you could get your hands on a pack that offers far greater comfort, a superior weight-to-volume ratio, and far more impressive overall quality of build.
Our top pick of alternatives would be the Patagonia Ascensionist for ultralight adventures, the Osprey Talon 44 for comfort, or the Outdoor Vitals Rhyolite for a more spacious option that beats the Flash even on price.
Sam Hardy is an outdoor enthusiast with a penchant for survival prepping. He writes about the great outdoors and his favorite equipment here.