Say hello to the future of hiking and backpacking. The men's REI Co-op Flash TT (Technical Terrain) boots keep you light on your feet with recycled components and design input from thru-hikers.
Linings feature 75% recycled polyethylene terephthalate (PET); collar foam is 70% recycled PET; overlays have 30% recycled TPU
100% recycled content in the webbing and laces
Vibram® Megagrip Litebase outsoles are engineered for durability and confidence on all terrain, from dusty gravel to muddy singletrack
REI Co-op brand is certified to The Climate Label; we actively fund efforts to reduce carbon emissions across our business and support climate projects around the world
From feedback to field testing, all of our gear is dialed-in by REI Co-op members. Their adventures informed every stitch and detail—making for better, longer-lasting gear.
Reviews
(37)37 reviews with an average rating of 4.3 out of 5 stars
21 out of 22 (95%) reviewers recommend this product
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5 Reviews 5 reviews with an average rating of 5.0 out of 5 stars
Super comfortable, waterproof, lightweight hikers
Peanut_strength
1 year ago
Received free product
I absolutely love these boots. I go through a pair of hiking boots about once every two years, and these are some of the best I've ever tried. I started wearing them for day hikes and now I wear them almost full-time as my day-to-day shoes in the wetter winter months for everything from hikes to walking the dog in the rain.
I've worn these for many day hikes on beaches in Washington and Oregon this winter and snow-free lowland hikes. I've put in a lot of miles with them and they've held up super well so far.
My favorite feature is how comfortable these boots are. They're honestly more comfortable than my day-to-day street shoes and by far the most comfortable hiking shoes I've ever had. The thick soles have some spring to them, so they bounce back a little bit on the trail. It's like having some built-in spring in my step. These boots are also SUPER easy to get on and off. That might sound minor, but it's huge for me. I have big feet (mens size 12 US), and getting some hiking boots on is a full production: loosening the laces, getting a shoe horn, pulling and grimacing, sometimes ripping a grab handle off a boot. These boots just slip right on. Amazing. I wish every shoe I owned was this easy to get on and off.
The other awesome feature of these boots: they're actually waterproof. I've had other boots that claim to be waterproof, but are closer to "water-resistant." Not these Flash boots. I've had rogue waves catch my feet in these boots, and as long as the waves don't get over the ankle of the boot, my feet stay totally dry. Same for rain. I've worn these on a beach hike where the rain didn't let up all day. My feet were just about the only part of me that stayed dry. As a bonus, you can also hose the shoes off without getting them waterlogged and worrying about mildew. This is helpful if you get them covered in sand or mud, or happen to step in something left by a four-legged hiker (yes, speaking from personal experience). They clean up really nicely. Even though they're totally waterproof, they still feel breathable. I have yet to have my feet overheat or get sweaty in these boots.
Also nice: the traction on these boots is excellent. They provide good grip on wet beach rocks and logs which are notoriously slippery.
It's worth noting that these shoes fit and feel like a sturdy trail running shoe. They don't offer the full ankle support of a traditional hiking boot. But, I'm fortunate that I've never had ankle issues and I haven't been using these (yet) for fully-loaded multi-day backpacking trips. So, for me, these boots provide the perfect amount of support for fast and light hiking adventures, as well as winter walks in town.
I absolutely love these boots. I go through a pair of hiking boots about once every two years, and these are some of the best I've ever tried. I started wearing them for day hikes and now I wear them almost full-time as my day-to-day shoes in the wetter winter months for everything from hikes to walking the dog in the rain.
I've worn these for many day hikes on beaches in Washington and Oregon this winter and snow-free lowland hikes. I've put in a lot of miles with them and they've held up super well so far.
My favorite feature is how comfortable these boots are. They're honestly more comfortable than my day-to-day street shoes and by far the most comfortable hiking shoes I've ever had. The thick soles have some spring to them, so they bounce back a little bit on the trail. It's like having some built-in spring in my step. These boots are also SUPER easy to get on and off. That might sound minor, but it's huge for me. I have big feet (mens size 12 US), and getting some hiking boots on is a full production: loosening the laces, getting a shoe horn, pulling and grimacing, sometimes ripping a grab handle off a boot. These boots just slip right on. Amazing. I wish every shoe I owned was this easy to get on and off.
The other awesome feature of these boots: they're actually waterproof. I've had other boots that claim to be waterproof, but are closer to "water-resistant." Not these Flash boots. I've had rogue waves catch my feet in these boots, and as long as the waves don't get over the ankle of the boot, my feet stay totally dry. Same for rain. I've worn these on a beach hike where the rain didn't let up all day. My feet were just about the only part of me that stayed dry. As a bonus, you can also hose the shoes off without getting them waterlogged and worrying about mildew. This is helpful if you get them covered in sand or mud, or happen to step in something left by a four-legged hiker (yes, speaking from personal experience). They clean up really nicely. Even though they're totally waterproof, they still feel breathable. I have yet to have my feet overheat or get sweaty in these boots.
Also nice: the traction on these boots is excellent. They provide good grip on wet beach rocks and logs which are notoriously slippery.
It's worth noting that these shoes fit and feel like a sturdy trail running shoe. They don't offer the full ankle support of a traditional hiking boot. But, I'm fortunate that I've never had ankle issues and I haven't been using these (yet) for fully-loaded multi-day backpacking trips. So, for me, these boots provide the perfect amount of support for fast and light hiking adventures, as well as winter walks in town.
Age:35–44
Weight:150–175 lbs.
Height:5'9"
Typical Shoe Size:Mens 12
Yes , I recommend this product
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Cornfed Mountain Man
Received free product
Tacoma, WA
Rated 4.0 out of 5 stars
good quality and comfort
1 year ago
These Flash TT hiking boots fit as expected. I'm a size 11. I am 6' and 160 lbs. I almost always wear light hiking boots / shoes for support and comfort in my career as a high school art teacher. I'm on my feet nearly all day during working hours. Other light hiker brands I have experience with include Lowa, Merrell, Sorel, Khombu (Costco), and Solomon.
These light hikers are very comfortable, but I do take off a star for causing a small blister on the top of my big right toe during break-in period. I have worn them at least 3 days a week to work for the past month as well as other urban "hikes" to local parks, grocery stores, and typical Costco shopping;-)
The fit is excellent for my feet - I run in Altras and like the wide toe box on those running shoes and these hikers feel similar (obviously, not a 'zero drop'). The laces tighten very smoothly and the tongue that is attached on the sides / edges gets into proper alignment easily upon lacing. The tongue and laces settle into place well also - the tongue stays properly aligned. The soles are tacky on a variety of surfaces but not too soft or spongy. Waterproofing is decent, but I've really not tested them in real mud. My feet do get hot and sweaty typically - Odor Eaters insoles fit fine and the shoes breathe enough to keep down excess interior moisture.
I've had other light hikers that rub hard on the heel (the Sorels), but these do not experience any movement when in town or on light gravel trails. I've not done any backpacking yet this year, but will be using these when the time comes this summer.
I did receive these for free as a product reviewer, but I would not hesitate to buy them - very nice comfort, fit, and finish.
Age:35–44
Weight:150–175 lbs.
Height:6'0"
Typical Shoe Size:Mens 11
Yes , I recommend this product
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Andy
Received free product
Redwood City, CA
Rated 5.0 out of 5 stars
The Do-It-All Lightweight Boot
1 year ago
Excellent lightweight hiking shoes. Immediately comfortable. Was able to walk 20+ miles in the first couple days with them without any blisters. Lightweight, but supportive enough and have great grip. Love that they're stylish enough that you can go from the trail and hit the town without feeling out of place. My new "go-to" boots for day hikes and short multi-day trips or weekend trips where I just want to bring 1 pair of shoes.
Age:25–34
Weight:150–175 lbs.
Height:5'11"
Typical Shoe Size:Mens 10.5
Yes , I recommend this product
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northface151
Received free product
Arizona
Rated 5.0 out of 5 stars
Excellent for quick and light hiking
1 year ago
I have really enjoyed these hiking boots. They are mid height with more casual hiking in mind. They are closer in feel to a running shoe than a hiking boot and are very flexible and cushioned. I don’t think they would provide enough support for backpacking or carrying heavier loads. As they have some built-in waterproofing, they do run on the warm side. Without any break-in period they have been remarkably comfortable without any hotspots/blisters forming. Traction has been excellent in various terrain, including rocks, loose soil, and mud. The Vibram sole has held up well so far in a desert environment. I wear a size 10 in Nike running shoes and this pair in a size 10 fits perfect.
Age:35–44
Weight:175–200 lbs.
Height:5'8"
Typical Shoe Size:Mens 10
Yes , I recommend this product
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kvharker
Received free product
Portland, OR
Rated 5.0 out of 5 stars
Slide, slide, slippity-slide? Not Anymore
1 year ago
At first I was skeptical of a hightop trail runner. Heavy, bulky, I thought. But when you pick them up for the first time they feel feather light. Lace them up and you immediately are transformed into a 4wheel drive, all-terrain vehicle. The traction is superb. My dog and I bomb down muddy hills, power walk through puddles, and ascend wet rock in these kicks. The shoes have kept me dry and sure-footed. Highly recommend!
Age:45–54
Weight:225–250 lbs.
Height:6'2"
Typical Shoe Size:Mens 12
Yes , I recommend this product
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HillStrider
San Diego, CA
Rated 2.0 out of 5 stars
Loser of the 5 boot challenge
1 year ago
I recently tested the following boots head-to-head. The testing was indoors (to facilitate returns), but included flights of stairs, a slant board and squatting. All boots were initially tested with their own insole and then with a SuperFeet Hike insole.
Pros: Good heel loop; Med-Hi tongue gusset, Decent construction & Vibram sole; Mediocre insole, but comfortable padding
Cons: Mediocre lacing pattern; High vol foot design
Thoughts: If you have "thick" feet (vs wide), this might be the shoe for you. I couldn't lace out the extra volume in this design. In spike of the Vibram sole, the only use I could think of for this shoe is park walking or well-graded fire roads.
Verdict: Cheap high-top walking shoe
Age:55–64
Weight:150–175 lbs.
Height:5'11"
Typical Shoe Size:Mens 9
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Kindbat
Michigan
Rated 1.0 out of 5 stars
Ammonia smell on outside after getting wet
11 months ago
I love these shoes so much. I have never had a better shoe for trail walking, rainy day walks with dogs, etc… in fact I thought I’d found the holy grail of waterproof shoe.
Now the negative part, we recently went on a long walk in the rain on groomed trails and my husband’s pair leaked. I put both pairs in front of a fan to dry and they dried quickly, but when I went to turn the fan off, I thought the room smelled like cat urine (we don’t have a cat). It turned out to be the shoes! Both pairs SMELL bad, as in the entire 1200 sq ft finished basement (even in totally different rooms) smelled bc of the fan circulating the air from the shoes. I did some research and apparently some shoes use materials and glues that give off an ammonia smell when they break down.
I’m not kidding when I say both pairs still smell terrible even after extensive attempts to clean them. I removed the insoles and laces, dunked everything in a diluted bleach solution, fan dried - still smelled. I tried again, but put them in a tote with baking soda on them after - still smelled. I tried again, scrubbed membrane on the top toe area because that seems to be the area with the most issue (for example, the membrane on the heel doesn’t smell) - they still smell! I even tried putting ammonia neutralizing animal urine spray on the bad areas after cleaning - they still smell.
It’s insane and it’s real.
I’m wondering if the toes got exposed to water more and the membrane has broken down faster? I have no idea, but I’m very bummed out because I don’t want to return them, but they’re now useless because they smell so bad. We’ve been wearing them on and off for 2 months (maybe like 15 times total). I got them on clearance. I wonder if REI has discontinued them bc of this issue bc they’re perfect otherwise. I hope they correct this issue and rerelease them bc I love them so much, except for that awful smell!
Age:35–44
Weight:125–150 lbs.
Height:6'1"
Typical Shoe Size:Mens 10
No, I do not recommend this product
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Vrooom
Portland, OR
Rated 4.0 out of 5 stars
Very comfortable, but not waterproof boot
1 year ago
Very comfortable shoes out of the box. I sized up after reading some found it narrow and am glad I did, it's still a close fit, but comfortable. Not waterproof, water resistant is probably a better description. Walk a mile in wet grass and your feet will be soaked, step in a single shallow puddle and you'll be OK. The sole in one shoe started making an odd noise after a few months, but it seems to have stopped and the shoe is holding together well. Tread wears quickly, but that's not a surprise as it's not a terribly aggressive tread. The comfort makes the shoe worth it.
Age:55–64
Weight:200–225 lbs.
Height:6'1"
Typical Shoe Size:Mens 11.5
Yes , I recommend this product
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dylan12899
San Luis Obispo, CA
Rated 5.0 out of 5 stars
Great first pair of boots
1 year ago
I bought these recently on sale for 70% off. This is my first pair of hiking boots I normally would just hike in running shoes and the employee at the store recommended these as a great hybrid between running shoes and hiking boots. They are extremely comfortable they have a nice feel when hiking and they offer a lot of support in the ankle. There is great arch support as well as a wide toe box which fits my feet perfectly. They also look really good they aren’t sad an brown the fun colors match just about anything i’m wearing on the trail.
Age:25–34
Weight:150–175 lbs.
Height:5'10"
Typical Shoe Size:Mens 10
Yes , I recommend this product
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tuffys1
Minnesota
Rated 5.0 out of 5 stars
Great lightweight hiker at the closeout price
1 year ago
I've been wearing these after receiving them for the last three days. Immediately comfortable. Good grip. These are not heavy duty hikers but for moderate trails they will be great. Vibram soles are definitely a plus. So far my only issue is the boots being shipped with laces from my childhood PF Flyers. I immediately replaced them with a medium weight corded hiking boot lace which was a huge improvement although I did have a little trouble getting the aglets (yes, that's what they're called) of the corded laces through the eyelets in the boot.
At the closeout price they are a great deal for lightweight hikers. I wouldn't pay the original price which is probably why they are on closeout.
