While down insulation still owns the field for thru-hiking jackets, synthetic-filled layers are making a dent in the category. As synthetic technologies become more eco-friendly and improve their warmth-to-weight ratio, the performance gap between down and synthetic will continue to shrink. And since synthetics are a lot more affordable and maintain insulating properties even when wet, they become more appealing with each passing year. Unlike down puffies, you can wear the best synthetic backpacking jackets both on-trail and in camp. Many models are built with breathable, wicking materials in the face fabric, lining, and insulation, allowing the wearer to use it as a breathable mid-layer without drowning in a puddle of sweat and decimating the insulating properties.
Enlightened Equipment Torrid Apex Jacket | Best Overall Patagonia Micro Puff |Best Patagonia Synthetic Jacket Arc’teryx Atom LT | Most Breathable Decathlon Forclaz Trek 100 | Best Budget Patagonia Nano-Air | Best Active Layer Rab Xenon | Most Wind-Resistant Montbell Thermawrap | Best Fully-Featured Ultralight Arc’teryx Proton LT | Most Durable Patagonia Nano Puff | Most Sustainable
You’ve got three options: blown-in, continuous filament, and short-staple.
Blown-in insulation, like PrimaLoft Thermoplume, is featherlike and feels most similar to authentic down, but is generally less durable and not as warm when wet compared to the competition.
Continuous filament insulation, like Climashield APEX, consists of a single long, continuous fiber coiled over on itself. Continuous filament is the most durable type of insulation. It doesn’t clump or migrate readily, is relatively compressible, and has enduring loft.
Finally, short-staple insulation consists of a lot of short, interlocking fibers. It is initially loftier and more compressible than continuous filament. However, loft tends to diminish more rapidly over time because it is also less durable than continuous filament.
Weight: Under 16 ounces Fit: A medium fit is your best bet for this layer. You should be able to fit a base layer and/or a fleece layer underneath and a shell on top. It’s common to hike / be active in a synthetic jacket, so be sure you can move freely in the garment and that the shoulders don’t restrict your range of motion. Hood: Adds significant warmth to any jacket but also makes it heavier and more expensive. If you opt for a hood, it should have a drawcord adjustment so you can cinch it down to shut out drafts. Shell Fabric: A durable, DWR-treated shell is optimal, as are reinforced cuffs and hem. Features: At least two hip pockets, which should be placed high enough to be accessible under a hip belt. Look for a model with a form-fitting hood that won’t eliminate your peripheral vision.
Note: This list is A) not in order and B) will continue to evolve as more products are released and tested. Product weights are based on size medium unless otherwise specified.
Best synthetic jackets for backpacking: Enlightened Equipment Torrid APEX.
Enlightened Equipment dialed down the ounces while still packing this jacket with enough synthetic insulation to make it comparable in warmth to down models like the Patagonia Down Sweater and the Outdoor Research Transcendent Hoody, both of which I have taken on many chilly trips. This jacket weighs several ounces less than my down-insulated jackets while still maintaining warmth when damp. The Torrid Apex fits true to size while being roomy enough for layering underneath and comes with two zippered hand pockets, a high collar, and a deep hood. The face fabric is rugged and has a DWR finish. The Torrid Apex clocks in with the greatest warmth-to-weight ratio on this list. Somewhat amazingly, it’s also the least expensive jacket on this list. -Maggie Slepian
Read our review of the Enlightened Equipment Torrid APEX jacket.
Warm, ultralight, affordable, customizable, US-made—this jacket has a lot going for it. Ultralight (2 oz. per square yard) Climashield APEX, a top-performing continuous filament insulation known for superior thermal efficiency and compressibility, lends the Torrid jacket an impressive warmth-to-weight ratio. The outer shell and lining consist of slippery-smooth nylon in a variety of fabric weights and colors. You can choose between seven, 10, and 20 denier nylon for the shell and seven and 10d for the liner. (Note: the stock Torrid jacket comes in 100% 10d nylon). You can also choose whether or not to put an adjustable hood on the jacket.
All Torrid jackets come standard with a full-length zipper, two zippered hand pockets, elasticized cuffs, a drawcord-adjustable hem, and DWR treatment. The jacket has a loose/baggy fit and runs slightly oversized to accommodate layers underneath. Raglan sleeves (connected at the collar rather than at the shoulder) enhance range of motion, essential in a jacket that can function as an active layer.
If you love the jacket but wish it was a tad warmer, check out our review of Enlightened Equipment’s Torrid Pullover.
Pros: Ultralight; customizable; warm; affordable; plenty of room for multiple layers underneath; high-quality insulation; made in the US. Cons: Baggy fit; lack of quilting can lead to gapping between inner and outer fabric layers; long lead time for custom jackets; thin materials may compromise long-term durability.
Best synthetic jackets for thru-hiking: Patagonia Micro Puff.
At 9.3 ounces, the Micro Puff is lighter than many down jackets. The jacket is exceptionally pared-down, with no drawstrings for the hood or the waist and no chest pocket. The Micro Puff has two zippered pockets at the waist and two zipper-less pockets on the inside. That’s it. The shell is DWR-treated Pertex Quantum, and the unique baffle patterns keep the insulation in place with minimal stitching and minimal cold spots. The hood is snug, with elastic taking the place of drawcords. While the face fabric is treated and durable, this is better as a mid-layer than an outer layer when the weather gets wet. –Editors
Read our full review of the Patagonia Micro Puff.
The Micro Puff’s 10d Pertex Quantum shell (ultralight, tightly-woven ripstop nylon) offers decent resistance to wind and water, especially since it’s DWR-treated to help the jacket shed light precipitation. The garment features 65g continuous filament Plumafill insulation (Patagonia’s in-house synthetic fill), comparable to 800-fill down in terms of loft and warmth. (By the by, the “65g” part references the weight of a one-meter-square sheet of that material).
The Micro Puff’s quilting pattern keeps the down-like Plumafill from migrating without having excessive seams. The cuff, hem, and hood of this jacket are elasticized (not adjustable) to seal out drafts. There are two zippered side pockets and two internal pockets for storage.
Pros: Plumafill insulation is comparable to 800-fill down; warmer and lighter than Patagonia Nano Puff; lightweight; windproof and water-resistant; minimal seams. Cons: Expensive; no shock cord adjustment for hem or hood.
Best synthetic jackets for thru-hiking: Arc’teryx Atom LT.
The Atom LT features 60g/square meter Coreloft Compact, a short-staple siliconized polyester insulation “that has undergone a special process which reduces the thickness of the material by 50%, without reducing its insulation value by the same amount,” according to Arc’teryx. All this polyester goodness is sandwiched between a DWR-treated, 20d Tyono nylon shell and a highly breathable, 20d Dope Permeair nylon liner (both are proprietary Arc’teryx fabrics). The material is colored with a dope dying process that improves colorfastness and reduces water consumption and emissions.
The updated Atom now features stretchy, polyester-elastane blend fleece side panels, which boost mobility and breathability. There’s also an adjustable, brimmed hood, stretch knit cuffs, and an adjustable hem. The jacket also has three zippered pockets: one internal chest pocket and two exterior hand pockets. Like many (most) Arc’teryx designs, the Atom LT has a relatively slim, athletic fit that looks great and cuts down on drafts. It’s still loose enough to accommodate a midlayer underneath.
Pros: Breathable; stretchy fleece side panels; 20d nylon fabrics are relatively durable; no quilting. Cons: Heavy; expensive; zipper can sometimes catch; helmet-compatible hood a bit too voluminous for non-helmet-wearing thru-hikers.
Best synthetic jackets for thru-hiking: Decathlon Forclaz Trek 100.
If you’re on a budget, it doesn’t get better than the Trek 100. It costs a fraction of the price of most jackets on this list, yet the weight, materials, and features are on par with the best of them. It may not be as durable as a top-shelf jacket, but it should be able to survive a thru-hike if you’re careful with it. Decathlon offers a refreshing level of transparency on the product page regarding materials and design—which, when a product seems too good to be true, helps to inspire some much-needed confidence. We also featured the down version of this puffy in our roundup of the best down jackets for thru-hiking, so be sure to check that out if you’re on a budget but also interested in real down insulation. –Editors
We really like that this jacket emphasizes sustainable materials and manufacturing processes without tacking on a price markup for being an “eco-friendly” product. The polyester insulation (generic; no fancy designer labels here) is 70% recycled, and Decathlon is using PFC-free DWR treatment on the 20d polyamide shell fabric while many high-end companies are still struggling to phase these toxic forever chemicals out of their water repellent lineup. The company also uses a more sustainable process to dye the fabrics in this jacket, reducing emissions and pollution.
The jacket packs into one of its own zippered handwarmer pockets–always a win—and features an adjustable hem. Decathlon says it will keep you warm down to 23˚F if you’re active while wearing it or 41˚F if you’re idle. There are so many variables in real-world conditions that it’s hard to give a jacket an accurate temperature rating (which is why it isn’t normally done) but there’s no denying that the Trek 100’s 4.4oz/square meter insulation is the beefiest on this list.
Pros: Inexpensive; reasonable weight; sustainable materials/manufacture; warm. Cons: Not ultralight; hood is not adjustable and can feel loose by some reports.
Best synthetic jackets for thru-hiking: Patagonia Nano Air.
The Patagonia Nano-Air fits into its own pocket, with a wicking face fabric and breathable insulation—ideal for wearing during higher output activities. It weighs less than 12 ounces, with durable construction and synthetic sheet insulation that makes it easier to wash and care for in the long term. The Nano Air’s insulation and 60-g FullRange fabric provide warmth without overheating and dumps heat to avoid moisture buildup. Stretchy side panels help with range of motion and prevent sweat buildup under your arms. –Editors
Although it works well as a camp layer, Patagonia designed the Nano-Air for active pursuits. The articulated design and stretchy fabric panels, hem, cuffs, and hood maximize the wearer’s range of motion. Even the insulation, Patagonia’s proprietary 60g/square yard FullRange polyester fill, is stretchy and breathable (and made with 40% recycled polyester). Because FullRange is a continuous filament insulation, the jacket should retain loft for years to come. The jacket’s 87%-recycled polyester shell is treated with relatively eco-friendly PFC-free DWR to provide mild weather resistance.
The Nano-Air is not a four-season jacket: there’s just a thin layer of insulation, and its slim fit precludes easy layering underneath. But by the same token, it’s breathable and not too hot to wear while hiking during cold weather, and it’s perfect as a standalone jacket in warmer climes. The helmet-compatible hood is not adjustable, though it is stretchy and trimmed with elastic. The Nano-Air has two zippered hand pockets and an internal zippered chest pocket. The jacket packs down into the chest pocket for easy transport in your pack.
Pros: Breathable; stretchy; packable; articulated patterning; Fair Trade-sewn with recycled polyester; PFC-free DWR. Cons: Slim fit doesn’t accommodate layering underneath; non-adjustable elastic hood and hem; expensive; not super warm; lacking warmth to weight ratio.
Best synthetic jackets for thru-hiking: Rab Xenon 2.0.
The Xenon 2.0 is $15 cheaper and about an ounce heavier than the original Xenon. This jacket stands up exceptionally well to wind, with an insulated baffle protecting the zipper where wind can sneak in. The internal zippered pocket acts as a stuff sack, and the insulation is recycled. Bonus points for environmentally friendly material sourcing. While this jacket is warmer than others on the list, the face fabric and insulation are less breathable than others on the list, making it a better choice for camp and less so for active wear. –Editors
The updated Xenon 2.0 now features recycled PrimaLoft Silver insulation instead of Rab’s in-house Stratus. While the lining is still Rab’s 20D Atmos ripstop nylon, the outer shell is now made of beefier, recycled 30D Pertex Quantum ripstop with a PFC-free DWR finish.
While the old Xenon had no baffles, the 2.0 has modest chevron-shaped quilting on the torso to help with breathability (historically an issue with this jacket) while retaining the baffle-free sheetlike construction in the shoulder area to maximize wind resistance.
The stretch-bound cuffs and hood seal out drafts, but the hood isn’t adjustable (sadness). The hem has a traditional shock cord adjustment. The Xenon has two zippered hand pockets and packs into its own zippered internal chest pocket.
One of our favorite features of the Xenon is its unique two-way zipper, which lets you unzip from the bottom. That way, you can wear the jacket like a cape, venting heat from the bottom while your chest stays protected. The 2.0 is significantly more fitted and flattering than the old Xenon, which was fairly loose and baggy. It’s still roomy enough to accommodate extra layers beneath, fortunately.
Pros: Recycled fabric and insulation; PFC-free DWR; excellent wind resistance; durable materials; two-way zipper; relatively affordable; packable; improved breathability Cons: Non-adjustable hood; relatively heavy
Best synthetic jackets for thru-hiking: Arc’teryx Proton LT.
The Arc’teryx Proton LT Hoody is another jacket that gets top marks for breathability. This is a piece you can feel confident wearing on-trail and in camp. The jacket is built with Fortius Air 20 face fabric that balances air permeability and weather resistance and is packed with Coreloft Compact 80 insulation to keep you warm at camp. The Proton can stand up to light snow and dampness, and the slim fit is an ideal mid-layer. –Editors
The Proton LT features Arc’teryx’s proprietary Fortius Air 20 face fabric, a breathable nylon-elastane blend that Arc’teryx says is 60 times more durable than the industry standard. The lining, meanwhile, is 100% nylon in the form of proprietary Dope Permeair 20. This isn’t a lightweight jacket, but it is warm: most of the garment is insulated with 80g/square meter Coreloft Compact polyester fill, the highest-destiny insulation on this list. We say most of the garment because the hood is filled with 60g/square meter Coreloft Compact instead (same as the Arc’teryx Atom LT above).
The jacket has an adjustable, helmet-compatible hood and hem and elasticized cuffs—also two insulated, zippered hand pockets and a delightfully roomy external zippered chest pocket. Designed with climbers in mind, the Proton LT’s gusseted armpits and articulated elbows aren’t altogether wasted on hikers, as these features translate to a notable increase in comfort and mobility.
One caveat to our “most durable” award: older versions of the Atom LT used Coreloft Continuous, a longer-lasting continuous filament insulation than the short-staple Coreloft Compact, which may lose significant loft after a few seasons of heavy use. Perhaps we should say “most abrasion-resistant” instead.
Pros: Durable face fabric; warm insulation; breathable; gusseted underarms and articulated elbows; roomy chest pocket. Cons: Heavy; expensive, short-staple insulation can de-loft relatively quickly.
Best synthetic jackets for thru-hiking: Patagonia Nano Puff.
The Patagonia Nano Puff is built primarily from eco-friendly materials, including a recycled polyester ripstop shell and packed with PrimaLoft Gold Insulation Eco, made from post-consumer recycled content. This jacket is one of the least-insulating on the list, ideal for warm weather and hot people (temperature-wise, that is, although the cut is very flattering). It also has a neutral fit for layering over and under. The hood is form-fitting, the face fabric is abrasion resistant and highly durable, and all materials are weather-resistant. This jacket is reasonably breathable for use as a mid-layer on the go. –Editors
The Nano Puff is the only jacket on our list that features 100% recycled polyester in both the fabric and the insulation, a reduced-emissions manufacturing process, and less-toxic, PFC-free DWR on the face fabric. (Though it’s worth noting that the budget-friendly Decathlon Forclaz Trek 100 is also a contender for the “most sustainable” award). The insulation in this jacket is of the short-staple variety, meaning it will have superior loft and compressibility initially, but loft will decrease over time because it isn’t the most durable insulation.
A brick quilting pattern crisscrosses the 20-denier polyester shell (22-denier for the liner) to stabilize the insulation. This pattern effectively shuts down any potential clumping/migration, but it also adds many seams that introduce cold spots to a garment that’s already pretty thin on insulation. The Nano Puff has elasticized cuffs, two zippered handwarmer pockets, and a zippered internal chest pocket. There’s also a drawcord-adjustable hem and a fixed, elasticized hood.
The jacket is on the long side and features a droptail hem (back is longer than front) to keep your bum toasty. It fits comfortably and has enough room for a midlayer underneath without feeling baggy. Thanks to the minimal insulation, it’s eminently packable as well. The Nano Puff isn’t ideal as a standalone jacket for cold weather, but it’s perfect for summer use or hikers who run warm but need just a touch of comfortable, lightweight warmth (and also want to do their bit for the environment).
Pros: Recycled materials, reduced emissions, and PFC-free DWR; packable; comfortable fit; decent breathability. Cons: Not that warm; lots of seams; hood not adjustable; expensive/heavy for the amount of insulation; insulation may de-loft relatively quickly.
Best synthetic jackets for thru-hiking: Montbell Thermawrap Parka.
The Montbell Thermawrap Parka is the second-lightest jacket on our list, after our pick for the overall best synthetic puffy: the Enlightened Equipment Torrid APEX. But although the Thermawrap is pricier and one ounce heavier than the Torrid, it also has more features. These include special, moderately stretchy insulation to enhance mobility, a zippered external chest pocket, low-profile quilting to stabilize the insulation, and a much more flattering fit. For those who wish to go ultralight without sacrificing features and functionality, the Thermawrap is the one. –Editors
Montbell’s Stretch Exceloft insulation comprises three different types and sizes of fibers to provide an optimal combination of resilient structure and fluffy loft. The fibers are siliconized to repel water, so the insulation will dry quickly and retain warmth when wet. Montbell claims their proprietary synthetic outperforms the competition in both thermal retention and “loft recovery rate” after repeated compression and expansion cycles.
The jacket is made from Ballistic Airlight nylon:15d in the sleeves and 12d in the main body. Ballistic Airlight is Montbell’s proprietary ultralight, calendered, hollow-fiber ripstop nylon–functionally, the fabric is very similar to Pertex Quantum. It maximizes wind/abrasion resistance and breathability while minimizing weight.
The Thermawrap features a DWR-treated shell and zipper, two zippered hand pockets and a zippered external chest pocket, and an adjustable hem.
Pros: Ultralight; stretchy; moderately breathable; affordable; many features considering the weight; decent wind resistance. Cons: Expensive; thin materials may compromise durability; not quite as ultralight or affordable as EE Torrid Apex.
Because we’re so incredibly intelligent, of course! Attractive, too. (Not to mention extremely humble).
But if that isn’t enough to impress you, there’s also the fact that everyone who contributed to this article is an experienced thru-hiker with thousands of on-trail miles under their belt. We’re gear nerds who love putting our equipment to the test on trails long and short, and we’ve tested dozens of puffies in pursuit of warmer backcountry days.
Moreover, we do our best to stay plugged into the trail community’s gear preferences (we are definitely those obnoxious people on trail who always want to know what everyone else is packing). That means our picks for the best synthetic jackets for backpacking aren’t just our opinions: they’re based on years of feedback from the thru-hiking community. Thanks to everyone who commented on last year’s list—we incorporate your suggestions and requests as often as possible. (Several worthy suggestions from last year couldn’t be included because the items have been discontinued, sadly).
Competence and backpacking proficiency personified.
Featured image: Graphic design by Chris Helm (@chris.helm).
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Ahh you guys missed the Outdoor Research Ascendant! It’s my favourite synthetic active midlayer – it was developed for the army, since soldiers can’t just stop and easily shift their layering. I love it because it keeps me comfy on trail over a pretty wide span of temperatures, plus it is pretty wind resistant. It’s insulated with Primaloft Alpha which is VERY snuggly. Its sleeves are designed so that you can scrunch them up if you are feeling a tad warm, and the pockets have no zippers, but they are just soo cozy that you don’t mind – they are genuine hand warmer pockets.
My Ascendant replaced my Arc’teryx Atom LT on trail – the Atom LT is a great jacket when on the move, but in camp the wind blows liberally through those stretchy fleece side panels, chilling you. I do also have a Patagonia Nanoair (I work at a gear store which I have been at for five years,) and I have not gotten to test it on trail, but it is comfy as heck and feels like a nice fluffy blanket when you wear it – love it!
The OR Ascendant’ll be coming with me on my next thruhike. However, because I am cold as heck, I will also be bringing my Mountain Hardwear Ghost Whisperer to layer over top in camp at night. (I have SUCH respect for people capable of taking just one midlayer, but I just can’t. I would freeze to death.)
Thanks for the tip about the Outdoor Research Ascendant! And just to be clear you are recommending their hoodie, not the jacket? As I’ve gotten more into backpacking and am hoping to complete an AT thru-hike within the next year or two, I’ve been trying to upgrade my gear and have been going back and forth about what mid-layer I want to get. had my eye on the Arc’teryx Atom LT but after seeing what you said about it not being sufficient when at camp I’m going to check out the Outdoor Research Ascendant! I also had my eye on the Patagonia Nano Puff but that just didn’t seem warm or sturdy enough but I could be wrong. Do you have any recommendations for a quality rain jacket/shell? I had my eye on the Arc’teryx Zeta SL, not sure if you have used that but I’ve always been a fan of Arc’teryx and it seems to get consistently solid reviews. Thanks again!
The Marmot Avant Featherless hoodie should definitely be on this list. I think it’s probably similar to the Rab Nimbus but also toasty warm, lightweight 17oz and easy to find at a discount. I got mine for ~$140. Love it.
I have had the Rab Xenon for two years now…..used it on my first attempt (failed due to old Navy injury flare up) AT thru hike…and countless shake down and day hikes. When receiving it…..I was skeptical of its ability to keep me warm. However……it has proved outstanding. I’m 65 now….I run cold. But with a significant base layer (thermal Patagonia capilene, R1, or EMS Techwick), it has taken me through snow, hail, sleet, high winds In comfort. But what really sold me…..it “wetted through” one mid-30s day during sleet and downpours in the Berkshires. I was convinced the jacket had ceased to provide any warmth due to it being soaked, so I removed it and packed it away. A half hour later…..the wind came on strong. I was still 3 miles from a safe location….thought “what the hell….at least it provides something to break the wind and get me home to some bourbon!” I put that soaked Xenon on and instant warmth! I was amazed! Now I was pushing it and working up significant body heat…..but I kid you not…..soaked through, that Xenon was providing me the warmth I needed! Still, after two years, my only complaint is that “wrong side of the road” British zipper!
Great to see Rab in this list, thanks for the review 🤙 The comment by “CAPT Gary Andres USN ret on Feb 14th is golden and we feel it needs a repost:
“I have had the Rab Xenon for two years now…..used it on my first attempt (failed due to old Navy injury flare up) AT thru hike…and countless shake down and day hikes. When receiving it…..I was skeptical of its ability to keep me warm. However……it has proved outstanding. I’m 65 now….I run cold. But with a significant base layer (thermal Patagonia capilene, R1, or EMS Techwick), it has taken me through snow, hail, sleet, high winds In comfort. But what really sold me…..it “wetted through” one mid-30s day during sleet and downpours in the Berkshires. I was convinced the jacket had ceased to provide any warmth due to it being soaked, so I removed it and packed it away. A half hour later…..the wind came on strong. I was still 3 miles from a safe location….thought “what the hell….at least it provides something to break the wind and get me home to some bourbon!” I put that soaked Xenon on and instant warmth! I was amazed! Now I was pushing it and working up significant body heat…..but I kid you not…..soaked through, that Xenon was providing me the warmth I needed! Still, after two years, my only complaint is that “wrong side of the road” British zipper!”
Looking over this list of items reviewed as well as the other reviews it struck me that it must be really disheartening to those looking to get into hiking and backpacking to see that virtually nothing recommended will cost less than ~ $200 +++. Of course not every piece of gear costs over $200. I see on another “cottage brands site” a company selling sweat rags for just $20.00 each. Ya, a sweat rag for $20 bucks. I guess that’s better than the $50 lightweight metal hash/crack pipe also for sale.
You have it all backwards on the Arcteryx line, Editors… the Proton is, by far, the more breathable of the two jackets, and the Atom is more durable. I own both. The Proton was designed as a high output jacket. The Atom is more of your in-camp jacket… though I stayed completely warm on the AT with my Proton. Please stop misinforming people on gear.
I thru hiked the AT starting in February 2018 with the Patagonia Nano Puff. And froze my butt off for the first 2 months. After the hike it was about as thick as paper and I sold it back to Patagonia as worn gear. On the PCT this year I used the Patagonia Micro Puff and that was clearly warmer and lighter. Since I was a Flip Flopper and due to various fire closures I found myself in the Sierra in October. I then switched to my LLBean ultralight hydrophobic down jacket. 13 ounces with 4 ounces of near waterproof 850 down. Kept me warm in snowstorms, rain and in my quilt on very cold nights. I would never buy a down jacket or quilt that didn’t use hydrophobic down. It’s extremely water resistant.
I have sort of the opposite problem — I tend to run too hot, especially once I’m past the “warm-up” phase. Over the years I’ve learned how to dial that in for bicycle camping trips (start out a little cold/uncomfortable, then warm up to the perfect long-distance comfort level). I’m still trying to sort it out for backpacking, which I just took up last year.
I have the Enlightened Equipment jacket, and it is AMAZING; it is stunningly warm for its weight, and fits me perfectly. The thing is, though, if it’s any warmer than about 25 degrees, I’m sweating bullets after five steps. 🙂 (And that is with wearing nothing more than a light long-sleeve layer beneath the jacket.) I would love to find something like this jacket that would keep me comfy on those somewhat raw 40-degree days.