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The Montbell UL Thermawrap jacket is the lightest and most affordable model we tested. All features have been minimized to make a light, clean, very compressible dedicated mid-layer. With no hood and no zippers to close the hand pockets, this a completely utilitarian piece for folks seeking ultralight performance. The UL Thermawrap is lighter than anything other insulated jacket we tested, but also significantly less warm.
REASONS TO BUY
Super light
Very compressible
Truly ultralight warmth for a mid-layer
REASONS TO AVOID
No zippered pockets
If you're looking for a more warmth and the ability to use your insulated jacket as an outer layer, check out the Rab Xenon X Hoodie. We believe The North Face ThermoBall Jacket is the best dedicated mid-layer jacket we tested, though it's more expensive than the UL Thermawrap and more appropriate for colder temps.
Updated UL Thermawrap for 2016
A new and improved version of this jacket was made available in 2016. The updates include the addition of zippers for the hand pockets and a zippered chest pocket. Montbell has added stretchy fabric near the wrists for a more custom fit. The fabric in this new version has an updated weave which Montbell says gives added breathability while still keeping the same warmth. The colors and styling have also been updated.
Scroll down for a more detailed comparison of the new UL Thermawrap vs. the older 2015 version.
Our Analysis and Test Results
New 2016 UL Thermawrap vs. The Old Version (from 2015 review)
Montbell has updated the UL Thermawrap jacket for the 2016 season to include zippered closure on the hand pockets, as well as a zippered chest pocket. The 2015 model had un-zippered hand pockets and no chest pocket. They also added stretchy fabric to the inside of the wrists, which helps to keep the wrists comfortably snug and lock heat in. Another updated feature is a new weave of the fabric that Montbell claims to give the jacket more breathability while still keeping the same warmth. The newer version has 40 g Exceloft insulation vs 50 g in the 2015 model. The Montbell website lists the weight of the new jacket to be 8.5 oz. This year's version also has 2-toned colors and contrasting zipper colors on the blue and red jackets. The MSRP has gone up from $129 in 2015 to $139 for the new model.
Check out a side-by-side comparison with the latest model from 2016 on the left and the older model from 2015 on the right.
The Montbell UL Thermawrap jacket - updated for the 2016 season.
Here's a summary of the key differences between the new UL Thermawrap and the previous version.
Zippered Pockets Added — Our reveiwers listed the main con from the 2015 version was that the hand pockets didn't have zippers. Montbell heard these concerns and added zippers. Also, they added a zippered chest pocket.
Updated Weave for Insulation Material — The 2016 version has 40 g Exceloft fabric (vs. 50 g in the previous version) but it has a new weave, which Montbell claims keeps it just as warm while increasing the breathability.
More Stretch Fabric at Wrists — The new Powder Bowl has dropped from five to four pockets. There are two hand pockets, one right back, and one on the right thigh. The previous model had the thigh pocket on the left leg. As you can see in the comparison photo above, the angle of the hand pockets has also been altered.
New Color Schemes — The 2016 UL Thermawrap comes in blue, red or black color options. Each of these options are two-toned, and the blue and red models have contrasting zipper colors.
Slight Price Increase — The new version is going at an MSRP of $139, compared to the 2015 version which was $129.
We haven't yet had the opportunity to test out the 2016 version and the text and ratings in this review still reflect the older version.
Hands-On Review
The Montbell UL Thermawrap Jacket is the lightest and most compressible piece we tested…but it's also the least warm. This is a perfect jacket for someone looking to replace their fleece mid-layer with something lighter and more wind and water resistant.
Performance Comparison
We found this jacket to be exceptionally warm relative to its weight. However, keep in mind that it's the lightest we tested and isn't that warm when compared to other products.
Credit: Brandon Lampley
Warmth
Montbell uses 50 g/m2 Exceloft insulation in this jacket, while the other lightly insulated models use 60-80 g/m2 varieties. This jacket does not have a hood and we found the wrist cuffs fit rather loosely, failing to seal in warmth. On the other hand, this jacket delivers an amazing amount of warmth relative to its light weight and the only thing we'd change is making the cuffs a bit tighter.
Weight & Compressibility
Here we have the defining attribute of this jacket; UL stands for UltraLight, after all. This feather weight model tipped the scale at 9.8 ounces, compared to the next lightest, the Mountain Hardwear Micro Thermostatic at 10.4 ounces. The Thermawrap can compress smaller than any of the others we tested, but it doesn't stow into one of its pockets (that would require an extra zipper). The small stuff sack included with this jacket is a nice addition, but doesn't provide the easy stowing of a pocket. The stuff sack is also relatively large; you could fit two of these into it.
The Thermawrap comes with a small, light stuff sack. For thruhikers, and others looking to compact and carry several clothing items, you could store a hat and gloves, or even a light rain shell in addition to the jacket in this stuff sack.
Credit: Brandon Lampley
Comfort
The Montbell UL Thermawrap, in its quest for ultralight warmth, has very few features aimed at comfort, but does offer great mobility. The underarm design lets your arms move around well without tugging the hem of the jacket up. One of our few complaints with this jacket's design is the collar. The front has a fleecy hood for the zipper, but there is a lot of material here and it tended to poke us in the bottom of the chin. This part of the ThermoBall's collar is more flexible and more comfortable. The Thermawrap's hand pockets are deep and warm but they don't have zippers; this, along with the lack of a chest pocket, makes this model uniquely minimalist. The main zipper pull is easy to grab and the wrist cuffs are low profile and comfy but not snug-fitting. Finally, there is no cord to snug up the hem. This jacket's overall lack of features makes it much more useful as a dedicated mid-layer.
A microfleece hood covers the zipper when the collar is zipped up, but we found it quite stiff. Montbell uses a similar cuff design to Arc'teryx, but the Atom's cuffs fit snugly while these are loose.
Credit: Brandon Lampley
Weather Resistance
Intended as a mid-layer, weather resistance is lacking in the Montbell UL Thermawrap. We found that its DWR coating worked well and did not degrade during our testing. Along with the North Face ThermoBall, it is one of two models with sewn-through construction and no additional lining; the stitching that secures the insulation passes through all layers of the jacket. Generally speaking, sewn-through construction leads to both poor water and wind resistance. Enjoy this jacket for what it is - an ultralight insulating mid-layer - and throw a shell over top for windy or wet weather.
Breathability
While warm air can pass through the sewn-through stitching of this jacket, the insulation and fabric do not lend themselves to good breathability overall.
Style
We awarded this jacket a high score for style. It has a trim, athletic fit, and the sewn-through stitching creates large panels, rather than the small ones seen on the ThermoBall and Nano Puff. The jacket looks great even though it is one of the least expensive.
This jacket's stitching creates large horizontal rectangles. We sized all our test jackets to give us the option of layering under or over a light shell, but one size smaller would fit this tester much better.
Credit: Brandon Lampley
Best Applications
This is a perfect light jacket for cool rather than cold conditions. We believe it's the best model we tested for thru-hiking and light backpacking. Throw it on over your T-shirt for camp in the evening and wear it under your ultralight shell in cold, rainy weather. Folks who wear a medium weight fleece as a mid-layer will love the lightweight warmth the UL Thermawrap provides when making the switch.
This jacket kept us warm and moved pretty well. Mobility testing on Flagstaff Mtn in Boulder, CO.
Credit: Brandon Lampley
Value
An excellent value at $130, this jacket could have won our Best Buy Award, but its ultralight weight and lighter insulation really put it in a class of its own in our test group. If you are looking for a great deal on a warmer jacket, be sure to check out the Outdoor Research Cathode Hooded Jacket, which won our Best Buy Award.
Conclusion
The Montbell UL Thermawrap is ultralight and warm for its weight. Purchase this jacket to use as a dedicated mid-layer. It is the lightest model we tested.
While we ordered this jacket in size large, to provide the option for layering over a shell, a medium would better suit its best use, as a dedicated mid-layer.
