SectionHiker.com Backpacking Gear Reviews and FAQs 
The REI Flash Jacket is a very thin nylon jacket that traps your body heat and prevents the wind from stripping it away. Also called a windbreaker or wind shirt, it’s much more breathable than a raincoat or a hardshell jacket, it only weighs a few ounces, and compresses down to the size of an apple. It’s an ideal garment to wear over a midlayer garment like a fleece hoody when it’s cool out or to prevent bugs from biting you during bug season when a heavier jacket is too hot. In winter, I wear one as an outer layer on 90% of my hikes because it’s so much more breathable than a rain jacket or hardshell.
Specs at a Glance
- Weight: 4.5 oz in a men’s XL
- Gender: Men’s and Women’s sizes are available
- Pockets: 5
- Hood: Volume adjustable at rear of hood
- Material: Recycled Nylon
- DWR Coating: Yes
The REI Flash Jacket is a gossamer-thin nylon jacket designed to trap your body heat when you’re actively hiking or exercising. It doesn’t have any insulation of its own but blocks the wind or cold air from penetrating your midlayer clothing and chilling you. You’ll be amazed at how much warmer you’ll stay when you’re wearing it.
The Flash Jacket is also remarkably breathable and wicking, meaning that it absorbs the perspiration you generate, both sweat and water vapor, and helps evaporate it without chilling you. I can literally feel dampness on the outer surface of the jacket when I’m hiking hard and climbing mountains, but I’m still nice and dry inside. While it has a mist-shedding DWR coating, it’s not waterproof like a rain jacket or hardshell.
The Flash Jacket is a little different from most windbreakers and wind shirts because it has a lot of pockets, five pockets in all. There’s a chest pocket capable of holding a full-sized Smartphone, two internal drop pockets for holding hats or mittens, and two external side pockets (unzippered) to keep your hands warm or carry extra stuff. This makes it an ounce or two heavier than many ultralight wind shirts and windbreakers, but it’s a tradeoff that provides the jacket with a lot more utility. Still, having a chest pocket for a phone is a really nice feature that I wish more windbreakers and wind shirts had. And of course, you can stuff the jacket into its chest pocket if you like.
The Flash Jacket comes with an adjustable hood, with a rear cordlock, so you can shrink the hood volume down to human size. It has elastic wrist cuffs to seal out the wind, although I wish they were a little larger so I could slide the sleeves higher up my arms when I want to release more body heat without taking the jacket off. There’s also an elastic hem adjuster so you can sell out drafts from below, along with a full-length front zipper for ventilation.
The Flash Jacket is made with thin recycled nylon. REI doesn’t publish the denier spec, but it’s very similar in texture and weight to the 15 and 20d fabric used on Patagonia’s Houdini Jacket and the Rab Vital Hoody. The Flash Jacket is also rated windproof up to 30 mph, which I can vouch for first hand on windy winter summits.
Recommendation
At 4.5 oz, the REI Flash Jacket is on the low end of the gear weight spectrum for windbreakers and wind shell jackets which is pretty impressive considering the amount of functionality and pockets REI was able to include. Despite those added features, it’s really quite a good buy and I’d definitely recommend getting yourself one, especially if you’ve never used a windbreaker or wind shell for hiking or backpacking.
Disclosure: REI donated a jacket for this review.
Updated January 2023.
SectionHiker is reader-supported. We only make money if you purchase a product through our affiliate links. Help us continue to test and write unsponsored and independent gear reviews, beginner FAQs, and free hiking guides.
I have two Patagonia Houdini’s that are in constant use year round. Both of them are L and if I wanted anything more than a light fleece under them, I would probably have to go to XL (which probably would make the sleeves too long).
Any comment on how the sizing is for this REI jacket? The hood adjustment and pockets make this look like a good replacement for a Houdini on colder days.
I wear an xl over a fleece hoody all the time and there’s plenty of room inside. I can also put a 200 weight fleece vest on over the fleece hoody and there’s still room inside the flash jacket to move freely.
I have 2 wind breaking jackets. One that fits extremely close to the body for cool temps. I wear this one under vests and fleece, with a synthetic wicking layer next to the skin. The second is large enough to allow cold weather layers underneath. I find a lamb’s wool sweater underneath in cold, wet climates a good option, especially if there are large amounts of physical activity involved. What you wear with minimal activity and with high activity will encourage layering adjustments, as perspiration management becomes important
Can you apply a waterproof spray to the jacket?
You can, but I wouldn’t. It’s really not intended to be a rain coat and you’d sweat too much inside if you tried to hike with it in rain. It’s better to use a rain jacket and a fleece pullover underneath. This jacket is meant as an external layer.
How does the size compare to the EE Copperfield wind shirt?
Its a little roomier in the torso.
Thanks for the review Phil. As usual well illustrated and written.
All the REI FLASH items I’ve owned have been top quality and well designed. Currently I have two FLASH insulated air mattresses, one for 3 season and one for winter.
My first two UL packs were FLASH UL models and I liked them – until the wonderful Osprey EXOS came along.
As for wind shirts/parkas I’m not a fan. I use tightly woven polyester or nylon shirts or my REI eVent parka. It’s just one less item to carry by making orate items serve the purpose.
I am a woman who would wear a M in the Flash jacket you reviewed. If I was to wear a fleece jacket underneath should I get a size Large???
I would try an M unless you have an unreasonably thick and oversized fleece jacket.
I would click through to REI and look at the measurements listed, and think about what has worked in the past. The jacket is not in the least bit stretchy.
Actually, it has a little stretch in the torso (she concluded after checking again).
I am wondering if “wind shirts” continue to provide wind protection when the DWR coating has worn off and they are “wetted out” from moisture. Thanks.
No. That’s why you still have to carry a rain coat.
Just picked up one of these with the 20% off coupon. I also want to give kudo’s to REI for including Tall sizes in much of their product line.
Just climbed Mt Washington in mine!
How would’ve the Copperfield performed compared to the Flash? Also which route did you choose-western or gulf side.
The Coppermine would not have breathed as well. I use it on colder days when I want less evaporation (breathability) and more warmth.
The Flash jacket was really perfect today, although you should know that the Copperfield has a better hood with neck toggles.
For Washington, we went up the Jewell. I really don’t like the east side in winter. Don’t know why people use it, although I guess it’s “cooler” for the guide services.
Others have said this is less breathable than current Houdini, yet you say it’s remarkably breathable. Can you throw a guesstimate cfm number at it? Houdini is around 5cfm.
Sorry – don’t have one handy. I think its certainly more breathable than a 10 cfm Copperfield and the Montbell Tachyon (who’s cfm I didn’t have on hand) but other than that I don’t have any good reference points. The problem is that the manufacturers and their suppliers change the fabric multiple times a year so any specs you might think you have are quickly outdated. Frankly, I plan to sell my Copperfield. This Flash Jacket is loads better.
I got an REI (women’s) Flash wind jacket based on your recommendation, and find it to be a very useful piece of gear. I prefer it to my old (now torn) Patagonia Houdini because it fits better, has pockets, and is sufficiently breathable.
Glad it worked out. I like it too.