Our Favorite Gear From the REI Co-op Flash Collection
Two Triple Crown thru-hikers break down the REI Co-op Flash pieces that actually earn a spot in our kits — from ultralight packs to sun hoodies and stretchy fleece
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June 19th, 2026
Home → Staff Picks
If you've shopped at REI in the last few years, you've seen the Flash name on everything from daypacks to tents to sun hoodies. So what actually is the Flash Collection? In short, it's REI Co-op's fast-and-light line — the house-brand gear and apparel built specifically for hikers and backpackers who want to cut weight without paying cottage-industry prices. "Flash" is REI's signal that a piece has been designed around the same priorities the two of us obsess over on a thru-hike: low weight, real durability, and a feature set that earns its place rather than padding a spec sheet.
The collection spans most of a backpacking kit. On the gear side, it runs from the budget-friendly Flash 22 daypack up through the Flash 55 backpacking pack and the ultralight Flash Air 50, plus Flash Carbon trekking poles and the Flash Air shelter family (the Flash Air 1 and 2 tents and the Flash Air tarp). On the apparel side, REI expanded the Flash sportswear collection in spring 2026, adding the Flash Pants, Flash Shorts, and Flash Shade Hoodie to layers like the Flash Hyperstretch Fleece and the Flash Air rain jacket. That sportswear push drew on insights from REI's Swiftland running line, tuning the fit and fabrics for people moving fast over long distances.
Two things set the line apart from a typical big-box house brand. First, sustainability is baked in rather than bolted on: you'll see recycled polyester and nylon, PFAS-free DWR finishes, and yarn made with LanzaTech carbon-capture technology, all under REI's Climate Label certification. Second, the gear is genuinely member- and field-tested — REI leans on feedback from the people actually using it (those reviews you leave on the REI website actually matter!), which shows up in the small, thoughtful details we kept noticing. The result is a line that competes surprisingly well with specialized ultralight brands while staying available at a store you can walk into, try on, and return to under REI's policy (with a member dividend on top).
That accessibility is exactly why we wanted to write this together. We've both hiked the PCT, CDT, AT, and AZT and tested a lot of gear that costs two and three times as much, so we don't grade on a curve. After going through the current lineup, these are the Flash pieces that genuinely earn a spot in our kits.
Summary Table
| Product | Picked by | Price | Key spec | Best for |
|---|---|---|---|---|
| REI Flash Shade Hoodie Men's Women's |
Liz Read why |
$69.95 | UPF 50+, 110 g/m² | Sun-exposed high-mileage days |
| REI Flash Shorts Men's Women's |
Naomi Read why |
$69.95 | UPF 50+, 4-way stretch | Warm-weather thru hiking & running |
| REI Flash Pants Men's Women's |
Naomi Read why |
$99.95 | UPF 50+, PFAS-free DWR | Brushy, buggy, or desert terrain |
| REI Flash 22 Pack | Liz Read why |
$59.95 | 22L, ~14 oz, sit pad | Day hikes, travel, summit bag |
| REI Flash Air 50 Pack Men's Women's |
Naomi Read why |
$299 | Under 2 lbs, UHMWPE | Ultralight thru hiking and backpacking |
Liz's Picks
REI Co-op Flash Shade Hoodie
REI's lightest, quickest-drying sun hoodie — a performance upgrade over the beloved Sahara, with a ponytail-friendly hood.
Price: $69.95
Fabric: 67% recycled polyester, 33% LanzaTech polyester
UPF Rating: 50+
Thumbholes: Yes
Weight: 5.3 oz women's, 6 oz men's
Sizes: XS–3X women's, S–XXL men's (some tall sizes also available)
The REI Co-op Flash Shade Hoodie ($69.95) is the sun hoodie I keep reaching for first on hot, exposed, full-sun days. It's REI's lightest UPF garment, built from a 110 g/m² performance grid fabric — noticeably thinner and faster-drying than the 150 g/m² Sahara Shade it sits next to in my closet. After a sweaty climb, it wicks and dries before I've finished my snack, which is exactly what I want from a layer I'll wear sunup to sundown. Seriously, the quick-dry makes this a great layer for paddling and even light swimming because it dries so quickly.
The woven (rather than chemically treated) sun protection is also a big differentiator for this sun shirt. The ShadeFactor 50+ fabric has UPF 50+ woven into the material rather than applied as a treatment, so it won't wash out over a long trail (and then get into streams). I also appreciate the thoughtful design details: a three-panel scuba-style hood with a vent/ponytail port (not enough sun hoodies have this!), thumbholes for back-of-hand coverage, and a high neck that keeps the sun off my collarbones.
That being said, to hit that UPF 50+ rating, the fabric is knit tightly, so it trades away some breathability you get from looser UPF 30 sun shirts. I haven't been anywhere super hot and humid recently, but it seems like the kind of thing you'd notice in that kind of climate. More noticeable is that the center-back length runs short. As someone on the cusp of S-M, I wish I'd sized up so my lower back isn't exposed when bending over to filter water.
I was pleased to see the Flash Shade Hoodie is also one of the more sustainable picks in the collection, made with recycled polyester and a LanzaTech carbon-capture yarn. For the price, it's an easy recommendation for anyone who's tackling sun-exposed miles.
Shop the Flash Shade Hoodie at REI
REI Co-op Flash 22 Pack
A 14-ounce, do-everything daypack with a removable sit pad and a hard-to-beat price.
Price: $59.95
Frame: Frameless
Hipbelt: Yes
Gear capacity: 22L
Weight: 14 oz
Exterior pockets: 4 + main compartment
Interior pockets: 2
Zippered side entry pocket: Yes
Reservoir sleeve: Yes
Fabric: 70-denier recycled ripstop nylon with polyurethane coating (bluesign approved)
The REI Co-op Flash 22 Pack is the daypack I recommend more than any other. It's a 22-liter pack that weighs around 14 ounces, almost in the ultralight realm, yet it costs less than most no-frills packs. That weight-to-value ratio is the reason I recommend this pack: you're getting a genuinely featured lightweight pack for the price of a cheap one.
The REI Co-op Flash 22 pack has a lid with a zippered pocket for snacks, sunglasses, wallet, and keys. It has two surprisingly deep side pockets that actually hold a tall water bottle securely. It took me a while to find the secret large zippered bonus pocket along the back panel. I've only seen this once on a daypack before, but I like the removable foam back panel that doubles as a sit pad. It's nice sometimes to have a dry seat at a summit or a lunch break somewhere muddy. I've seen that on backpacking packs before, but not so much on day packs. As a frequent hose + bladder user, I'm stoked that it is hydration-compatible, with an internal sleeve and exit ports for the sip tube.
Fit-wise, it's one size, built for torsos from about 16 to 21 inches with a hipbelt that handles waists from 26 to 42 inches. I've passed this pack around between hiking partners of very different sizes, and it adapts well, though taller folks at the top of that range may find it runs small. The mesh shoulder straps wick sweat and have enough padding for the kinds of loads you can fit in here (i.e., some layers, snacks, and water). It also has a tuck-away hipbelt to make it more packable for a luggage handle pass-through.
It's worth noting that with little internal structure, it goes floppy when empty and can take on a barrel shape if you overstuff it. It’s ultralight, but that means it has thin fabric that will require more care and less bushwhacking than burlier packs. But for day hikes, summit pushes, travel, and as a packable summit bag inside a bigger pack, this is as good as it gets for blending weight, features, and price.
Shop the Flash 22 Pack at REI
Naomi's Picks
REI Co-op Flash Air 50 Pack
REI's lightest backpacking pack yet — UHMWPE fabric, a roll-top design, and thru-hiker DNA
Price: $299
Weight: 1 lb, 12 oz to 1 lb, 15 oz (depending on size and gender)
Maximum load: 25 pounds
Frame: Internal
Gear capacity: 50L
Material: UHMWPE ripstop nylon (87% nylon, 13% polyethylene; bluesign approved)
Reservoir compatible: Yes
Exterior pockets: 8 + main compartment
Sizes: XS, S, M women's; S, M, L men's
The REI Co-op Flash Air 50 Pack ($299) is REI's most credible swing at the ultralight backpacking market, and as a thru-hiker, I've been impressed by how much they got right. Under 2 pounds, it's the lightest backpacking pack REI has ever made, built from UHMWPE (ultra-high-molecular-weight polyethylene) ripstop nylon, a material in the same family as the cottage brands' materials. It's surprisingly durable for its weight, with a PFAS-free DWR that helps water bead up and roll off rather than be absorbed by the fabric.
It was surprising to me how much REI got into that sub-2 pounds:
Two functional hipbelt pockets that are big enough for my iPhone Pro Max
A 3D contoured hipbelt that's incredibly comfortable
A ventilated back panel
A top Y-strap for a foam sleeping pad, bear canister, or a bag of chips
A removable mesh pocket on the shoulder strap that also fits my phone
Forward-placed water bottle pockets that are large and easy to access
Two large side pockets that fit my tent
A decent-sized kangaroo pocket
Daisy chain and attachment loops
Hydration tube port on either side of the pack
I tested the men's large because I have a long torso, and REI says it has a capacity of 3,112 cubic inches (51 liters). In reality, the capacity felt like much more than 50 liters to me. I seriously could not fill it up.
You can't expect a full-featured pack at this weight, but my verdict is that the REI Flash Air 50 delivers way more than I was expecting for its weight. If you're looking to step down in weight from a traditional 4+ pound pack without spending $600+, it's one of the easiest weight and cost savings options you'll ever buy.
Coming from years on the PCT, CDT, and AT, I'd put it this way: it's not the very lightest pack on the market, but you can legitimately get your base weight to 10 pounds with this pack.
Shop the Flash Air 50 Pack at REI
REI Co-op Flash Shorts
Featherweight, four-way-stretch hiking shorts with UPF 50+ and pockets that actually hold your stuff.
Price: $69.95
Style: Pull-on with drawstring waistband
Fit: Relaxed
Fabric: 87% nylon/13% spandex (bluesign approved)
UPF Rating: 50+
Pockets: 4
Inseam: 5" women, 7" men
Weight: 5.3 oz women, 5.6 oz men
Sizes: XS–3X women, S–XXXL men
Liner: No
I alternate between hiking pants, hiking shorts, and hiking skirts, depending on where I'm hiking and the expected conditions. As someone who was used to wearing more traditional, heavier hiking shorts, I was shocked when I tried on the REI Flash Shorts in the dressing room. There was no question that these were coming home with me. They've become my default hiking shorts.
Functional pockets are nonnegotiable, and the Flash Shorts deliver:
Two front drop-in hand pockets
One small stash pocket inside the left-hand pocket
One zippered pocket inside the right-hand pocket (men's is located on the thigh)
There are no back pockets or zippers, which I like because they tend to interfere with the backpack's hip belt and can cause chafing. The small stash pocket is perfect for keys and keeps them in place and bounce-free.
I love the lightweight, four-way-stretch fabric that moves with me on steep step-ups and scrambles, and it dries fast enough that a creek crossing or a sweaty afternoon is a non-event. And the fabric doesn't get that sticky, clammy feel from sweat that sometimes comes with synthetic material.
The waistband, upper back panel, crotch gusset, and pockets are all made with REI's Swiftland Grid fabric. The Grid fabric features a perforated texture to enhance breathability and ventilation in these crucial areas that tend to get sweaty.
I also like the pull-on waistband style. There are no buttons or zippers that could potentially cause chafing with a backpack hip belt. The internal drawstring allows for adjustments as I lose weight on a thru hike.
The cut runs generously through the leg, which I love — there's no crotch bunching and plenty of room to high-step over blowdown without feeling pinched. If you're between sizes, the drawstring gives you a forgiving range, and I'd lean toward the smaller size for a trimmer fit. The generous cut also means that if there is any breeze at all, you feel the air flow, and it's instantly cooling. I have friends who also trail run in the Flash Shorts (who are very picky about what they'll run in).
They also carry UPF 50+ sun protection, which matters more than people think for the backs of your legs on long, exposed ridge days. Between the sun coverage, the stretch, and the quick-dry fabric, these have become my warm-weather hiking and trail-running default. Pair them with the Flash Shade Hoodie, and you've got a head-to-knee sun setup for under $140.
Shop the Flash Shorts at REI
REI Co-op Flash Pants
Stretchy, sun-protective hiking pants that balance weight, durability, and all-day comfort.
Price: $99.95
Style: Pull-on with drawstring waistband
Fit: Relaxed
Fabric: 84% nylon/16% spandex (bluesign approved)
UPF Rating: 50+
Pockets: 4
Inseam: 30" women, 31" or 34" men
Sizes: XS–3X women, S–XXXL men
Weight: 7.8 oz women, 8.1 oz men
In the desert or if there's any chance of overgrown trail or bushwhacking, I'll opt for hiking pants. After my experience with the REI Flash Shorts, I went back to REI to try on the REI Flash Pants. These are REI's fast-and-light hiking pants, and they hit the sweet spot between a true ultralight pant that snags on everything and a heavy-duty pant that bakes you in the sun with no ventilation (hello, heat rash).
Functional pockets are a non-negotiable for me, and finally something that manufacturers are finally getting right with women's hiking pants:
2 large drop-in hand pockets that fit my iPhone Max
A stash pocket inside the right drop-in pocket
A zippered thigh pocket on the right that also fits my iPhone Max
One minor quibble: I actually prefer the stash pocket on the left, as with the Flash Shorts. With the zippered pocket on the right as well, that makes 3 pockets on the right and 1 on the left with the Flash Pants.
Similar to the Flash Shorts, there are no pockets or zippers on the back so as not to interfere with a backpack hipbelt.
The fabric offers UPF 50+ sun protection plus a PFAS-free DWR finish, so passing showers or morning dew bead up instead of soaking in. The PFAS-free part matters to me — it's the right direction for the industry, and REI is one of the bigger players making the switch.
The four-way-stretch fabric is highly breathable and moves freely, so they don't feel like a compromise on hot days.
While they may not win any style competitions, I actually like the slightly baggy, airy fit. I find that tighter-fitting pants feel hotter because there is less air movement. The Flash Pants have excellent air circulation, which helps keep the heat rash on my legs at bay. The legs taper to the ankles and also have a cinch cord if you want to lock them down even further. I was skeptical of this feature, since I thought the cinch cord could get caught on grasses or branches at the ground level (it's happened to me before). But REI added a cord-keeper to prevent this – another thoughtful detail.
The Flash Pants use the REI Swiftland Grid fabric on the waistband, pockets, and gusseted crotch areas. The Grid fabric has perforations to help with ventilation and moisture management. It extends 12" down the inner thigh, providing even better airflow.
The pull-on waistband works well with a backpack hipbelt, so there are no pressure points. The internal drawstring dials in the fit well.
All that being said, my top criteria for hiking pants is comfort and freedom of movement. And this is why I bought the Flash Pants – they are incredibly comfortable and the 4-way stretch fabric provides some of the best freedom of movement I've tested in a hiking pant.
One more quibble – I wish they came in a lighter color. It's easier to spot ticks on a light background, which is why I won't wear black hiking pants anymore.
The Flash Pants have become my go-to shoulder-season and desert pants, where I want sun coverage, abrasion resistance against brush, and breathability all at once. The durability-to-weight balance is excellent, and at $99.95, they undercut a lot of the technical competition.
Shop the Flash Pants at REI
REI Co-op Flash Hyperstretch Fleece Jacket
A stretchy, hard-face fleece that moves like a performance hoodie — and frequently goes on deep discount.
Price: $99.95
Fabric: 54% recycled polyester, 35% nylon, 11% spandex (bluesign approved)
Pockets: 2 zippered hand pockets
Hood: Yes
Thumbholes: No
Fit: Athletic
Fleece weight: Medium
Sizes: XS–3X women, S–XXXL men
Back length: 25.5" women, 27.75" men
Weight: 11 oz women, 13 oz men
I wear a fleece jacket almost every day for 8-9 months a year, and I've gotten pretty picky about the fleece I'll wear. The REI Co-op Flash Hyperstretch Fleece Jacket is my go-to fleece jacket for just about everything in temperatures down to 40F. With 11% spandex in the fabric, the mobility is excellent; it moves with me so completely that I can swing my arms, crouch, and reach without feeling like I'm wearing a jacket at all. That stretch is the whole appeal for me. I legit wear this fleece jacket almost every day in winter.
I also really like the hard-faced fleece exterior. Nothing irritates me more than spending a lot of money on a fleece jacket that starts pilling immediately and looks like something you've had for decades. The Flash Hyperstretch is not that. The hard-faced exterior is smooth and still looks new, even after 18 months of almost daily use. The smooth exterior also means it's easy to pull a rain jacket over it, which isn't the case with brushed fleece jackets.
The design feels more like a performance hoodie than a traditional fleece. The brushed interior stays soft and cozy against my skin even if I sweat. A scuba-style hood with an elastic edge stays put in wind, a wind flap behind the full zip cuts drafts, and a drawcord hem plus elastic cuffs let me seal in heat when I stop moving. The zippered hand pockets are big enough for my iPhone Max. And the hip-length cut stays down under a backpack's hipbelt instead of riding up.
Two honest caveats. This is a lightweight-to-midweight fleece tuned for mobility and breathability, so it sacrifices some outright warmth — I treat it as an active layer, not a standalone insulator for low-output cold. I also wish it had thumbholes.
I've found that it has kept its size and shape well through repeated washings. Although it says tumble dry low, I recommend line drying it (as I do with all of my technical apparel).
This fleece goes on sale constantly, sometimes dropping well below half price. At full retail, it's a solid value; on sale, it's one of the best technical-fleece deals out there.
Shop the Flash Hyperstretch Fleece Jacket at REI
FAQ
What is the REI Co-op Flash Collection?
The REI Co-op Flash Collection is REI's fast-and-light gear and apparel line, built for hikers and backpackers who want lower weight without cottage-brand prices. It spans packs, trekking poles, shelters, and sportswear, and uses recycled and lower-carbon materials throughout.
Is REI Flash gear good for thru-hiking?
Yes. Several Flash pieces are well-suited to thru-hiking, especially the Flash Air 50 Pack (REI's lightest backpacking pack) and the Flash Carbon Trekking Poles. The Flash sportswear line was developed with input from fast-and-light hikers and backpackers.
How much does the REI Flash Air 50 pack weigh?
The REI Co-op Flash Air 50 weighs under two pounds and is REI's lightest backpacking pack. It's built from durable UHMWPE fabric and comfortably carries loads up to about 25 pounds.
Is the Flash Shade Hoodie better than the Sahara Shade Hoodie?
For performance, yes. The Flash Shade Hoodie uses a lighter 110 g/m² fabric that's cooler and faster-drying than the Sahara's 150 g/m² fabric, while maintaining UPF 50+ sun protection. The Sahara is softer and stretchier for everyday wear.
Does REI Flash gear go on sale?
Yes, frequently — especially apparel like the Flash Hyperstretch Fleece, which regularly drops well below retail during REI sale events. REI Co-op members also earn an annual dividend on full-price purchases.
Why You Should Trust Us / About the Authors
Liz Thomas
Liz Thomas is an award-winning Los Angeles-based writer and Editor-in-Chief of Treeline Review. A former Fastest Known Time (FKT) record holder on the Appalachian Trail, Liz came to Treeline Review from New York Times/Wirecutter, the New York Times’ product review site, where she was a staff writer on the outdoor team.
Liz has talked gear on Good Morning America (TV), in The Wall Street Journal, The Guardian, Buzzfeed, Men’s Journal, Women’s Health, Gizmodo, and Outside Magazine.
To test the Six Moon Designs Lunar Orbiter Tent, Treeline writers backpacked on the Idaho Wilderness Trail. We also camped for a month in total in the Sierra using the Lunar Orbiter and used it on hikes in the San Gabriel Mountains and Anza Borrego Desert State Park in Southern California. We also used it through multiple days of extreme wind and rain storms in the Columbia River Gorge in Oregon.
You can read more about Liz at her Wikipedia page here or on her website. See all her Treeline Review articles on her author page.
Naomi Hudetz
Naomi Hudetz is co-founder and director of analytics and digital innovation and leads business strategy and revenue operations for Treeline Review. She brings decades of private-sector experience in project management, budget and pricing projections, and long-term business vision, strategy, and goals.
Naomi left her corporate career to pursue her passion for the outdoors. She received the Triple Crown award for hiking for completing the Appalachian Trail, Pacific Crest, and Continental Divide Trails and has hiked numerous other distance routes including the Great Divide Trail across the Canadian Rockies (twice), Grand Enchantment Trail, Pacific Northwest Trail, the Arizona Trail, (most of) the Idaho Centennial Trail, the first known thru-hike of the Blue Mountains Trail, and the Oregon Desert Trail. She recently bikepacked the Great Divide Mountain Bike Route.
She previously served as Treasurer of the American Long Distance Hiking Association-West, and is currently on the board of the Continental Divide Trail Coalition. She’s based in White Salmon, Washington.
