I’ve used Xenon jackets as my go to puffy for the past 4-5 years working/playing in the backcountry of AK and the SW. The jacket is very light, warm for its weight and surprisingly durable for the thinness of its exterior material.

However, the zipper sucks!!! It has tiny teeth that inevitably fail in 2-ish years of normal use. If Rab would change the zipper to a normal-toothed zipper, this jacket would be a 5!

Can't be beat for lightweight warmth, it packs up small and clips nicely onto a harness. It's not a durable outer material for actually climbing/hiking in, but I'm willing to sacrifice some rip resistance for weighing less than 13 ounces. Works great under a light shell (like the Pata Alpine Houdini) in wet conditions. I keep buying this one. The fit is great for me.

Wow, this jacket was a disappointment from the get-go, simply because the fit is poor and sloppy, and not what I'm used to with Rab jackets. The sleeves are huge in the bicep area, even if you're planning to layer this jacket, which I wasn't. I can put four of my bicep in a single arm of this. The whole arm is much to large and sloppy, which would make for a poor design in active use, increasing the likelihood you'd snag and rip it.

The jacket also runs WAY long, even if you're a tall person like I am - I'm 6'3" with a longer than average torso - this thing is gross long, and comes down below my crotch and way below my butt cheeks, neither of which is appealing in the least.

Suffice to say this went back for a refund.

Without a doubt this has become my “go to” warm up layer here in NH. Amazingly light, packs small and incredibly warm make it perfect for hiking. I replaced my fleece with this jacket saving weight and room in my pack. Climashield has proven its worth over and over in our cold wet environment. The pertex shell sheds light moisture. The hood, although “unique” looking is functional and warm. I use climashield now in my sleeping bag and my puffy, it’s the best insulation out there. The left zipper is different but then again so is driving on the left side of the road, you get used to it. I highly recommend this jacket.

I live in the Northwest and rain seems to come at any time so down is only practical in the mountains mid summer, or the dead of winter. I have had several down jackets and many synthetic jackets. This jacket is the best of both worlds! Like other reviews stated it doesn't breathe as well as the black diamond first light hoody or the competing Patagonia version of that jacket. That said it is a MUCH warmer jacket. Over the years of Alpine climbing I have found that I rarely hike in my insulated jacket, so essentially my jacket becomes a belay parka or for when stopped and taking a break. This jacket fits that bill perfectly. It is ultra light (feels like a down jacket in hand), the DWR is excellent, still very warm when wet from rain and leaking through (not suppose to be a rain coat).
Liner is smooth which means it slides on over my Patagonia R1 perfectly. The belay zipper allows the Hem of the jacket to keep your backside warm while having good access to your belay device and harness. No more bunched up jacket between you and your ATC. I didn't realize how much I would appreciate that feature, and can't believe other brands don't add it. So over all this is by far the best synthetic jacket on the market in my opinion, especially if you run a little cold like me.
I'm 5'6" and weigh 149lbs athletic build. The small was to tight around the chest, but the sleeves on the medium allowed air to blow up sleeve (easily remedied with a little stitching to fit my dainty wrists 😀) since the slight modification this had been the best insulated jacket I've owned ever! Oh yeah I forgot to mention that after being in a down pour and water leaking through, the jacket dried out in about 45 minutes! If you have been looking at this jacket and noticed it rarely goes on sale, there is a reason for that. It's simply amazing! If in the market, buy this jacket!

I wear this jacket for several winters now in Boston. It is light and warm. I go in the snow and rain with it. I bicycle with it. Just an excellent material. Like it very much.

I wear this under my hardshell on cold days while skiing. Also wear it on chilly fall days when I'm out on the river.

I was worried it was a little too techy looking when I first opened it but this jacket has quickly grown on me. Taken it camping on the AT and was perfect for sub 30F mornings, the hood looks a little ridiculous but is super effective at sealing heat in and makes a big difference. I just wore it in Michigan working outside all day in 24F with high winds and was astounded at how well it blocked the wind and kept me warm with a wool base layer and microfleece underneath. I kept waiting to pull out the down but never did!
The shell seems pretty thin and I worry about doing any bushwhacking in this jacket but to its credit there are no signs of wear whatsoever. packs up small and light with no effort. 6' 180 with broad chest and shoulders and large fits me perfectly, handsome cut but not too tight in the midsection.

The jacket is nice, warm, and can be very comfortable if the seam under the armpit wasn’t so high up. It’s quite annoying for it to be all up on my armpit. I read that these are the same problems with the other rab jackets too. If the seam weren’t so high up, this thing is definetly a top 3 best synthetic mid layer out there

This jacket is an improvement from the Patagonia Nanopuff because it doesn't have all that stitching. This creates larger air pockets in the jacket thus creating a larger thermal layer to trap body heat and warm you up. Also, the stitching squares aren't there to get snagged on things. The jacket has a little extra insulation on the front body which I am not complaining about. I have at least 3 RAB jackets and they are VERY high quality but keep in mind, they are a European company so it will have a left-handed zipper and European cut.

This is a great fitting warm jacket for layering

If you like the Nano-puff jacket but want something that will cut the wind a little bit better then you should go with this. It comes in at the same weight and fill of insulation but since it doesn't have the stitching and is one continual piece it will stay warmer (keeping your heat in, and the wind out)
The hip pocket has a stow tag for clipping onto a harness. I'm 6' - 165lbs I went with a medium and it fits pretty well. If you want to layer more underneath you may want to go with Large.
If you have any questions,
email me: wbowen@backcountry.com or give me a call: (801) 204-4571

I was leaning towards buying the new Patagonia Micro Puff hoody but got a great deal on this Rab jacket that I couldn't pass up. So far I am super impressed. The jacket feels great, packs up very small, and fits well (I'm 5'11" 185lbs athletic build and got a large). My only criticisms are that the midsection is a tad boxish and the zipper is the opposite of what I'm used to. I won't get a chance to wear it in the cold for another month or so and will try to update my review then.

To continue my quest to wast.... I mean invest more money on climbing, I started ice climbing last winter. So far, I only had to sell my left kidney and what I find at home yet don't expect. But I digress.
I quickly realized I don't have a good midlayer/outerlayer jacket, because I was shivering during belaying. After asking around, I picked Xenon (not this one, I bought BackCountry exclusive one, because it was cheaper). So far, I love it and it saddens me that I have to put it away, because winter is over.
It is really light, yet surprisingly warm. Maybe too warm.
And there lies it's only fault: it's too good of insulator and not breathable.
But it's hella better than freezing.

Rab comes through again with a smart, USABLE, versatile jacket. Quality is there too. Lightweight, more of an athletic fit (you can put light layers under it just fine); compressible in the backpack or ski bag for layering under a shell. As a layering jacket, if you find that down is just too much heat, this is your other alternative. No hybrid fabrics on sides or pits to dump heat quickly but overheating hasn't been a problem. And don't underestimate the power of Pertex Quantum as the outer ultra-lightweight fabric--very strong, wind resistant, water resistant, and helps hold in the heat.

I own lots of Rab clothing as I'm 6'4" 175 and their size large fits great- long arms and an athletic fit in the midsection. If you're tall and slim u know what I'm talking about... I expected the same with this jacket but was disappointed to find the fit more "regular" and not slim fitting in the mid-section thus greatly reducing its thermal ability (I've learned my lesson with other brands). I returned it. However if you looking for a synthetic jacket, this one has been voted the #1 synthetic jacket by Outdoorgearlab for the past several years so I have no negatives against its quality/thermal ability.

I have lightly used the jacket so far and it seems very warm and packs down small. I did extensive research before this purchase and it seems to be all it's cracked up to be. I want to note that the color ebony looks more like dark blue. I asked several people what color it looked like to them and they all said navy blue. I always wear medium shirts and that's what size I bought. It's a nice slim fit. I wouldn't be able to wear too much underneath it.

I purchased this to be used as a backcountry skiing/climbing belay jacket. Unfortunately it's not winter yet, so I haven't been able to test it out in the snow. On the other hand, it's been awesome for chilly days in the office and those frigid fall mornings in the Uintas. I can already tell it's super light weight and will pack away well.

This was a daily wear jacket in NYC for the winter of 2015. For temperatures below 40, the jacket alone is not sufficient if you are just wearing a button down shirt or sweater.

The jacket is very attractive looking, the orange lining on blue works very well.

Pockets are generously sized (and perfectly lined), and hood is nice and snug. Fit is normal, not slim. I am 5'8, 155 with a slim athletic build; small fits decently. Arms are a bit too long for me, and that is usually not the case for my clothes.

I've taken it camping a few times, and it's great to be able to throw a synthetic into the washer without having to worry about it. No snagging on branches too - which was a nice surprise.

For the price, if you are looking for lightweight, decently warm jacket that packs well - this is a solid choice (esp at current discounted prices).