Synthetic Midlayer Jacket Review

This midlayer jacket review keeps growing, and we’ll have more to come, but the following review of three jackets gives you a snapshot of the versatility and broad spectrum of fabrics and focuses that companies are providing.

Years ago, before the advent of new lightweight breathable insulations, like Polartec Alpha, we would have to layer up with bulky fleece under our shells or puff jackets. Fleece is a great insulator, but it lacks good wind resistance and therefore does not lend itself to being a good outer layer on windy days. The new ultralight insulations look like feathery fleece, but act to trap heat more like down. These new hybrid jackets create a ‘micro climate’ with an incredibly wide temperature range. Worn over a super light wool or synthetic base layer, they stay on comfortably throughout a wide range of conditions, keeping you warm, dry and fully mobile.

We picked jackets that have a modicum of lightweight insulation but also plenty of stretch, either in panels or the actual shell fabrics (inside and out). These jackets are unique in that they work extremely well as an outer layer on days that are not super windy but cold enough to need core warmth. They are incredibly versatile and a must for every mountain person’s quiver, whether for climbing, ski touring, trail running or most any active mountain pursuit. We put them to the test rock climbing and dry tooling as an outer layer, and ski touring and ice climbing as a mid layer. 


Proton Hoody

Price: $350
Weight: 11.3 oz. med
Fit: Trim fit, true to size, and layers easily under and over it.
Fabric: The shell fabric is silky and light, stretches nicely and allows moisture to easily escape to its surface and dry quickly. The insulation is the perfect amount for super cold skinning with just one layer underneath. It breathes and moves moisture out effectively but keeps us warm and dry all day. We never had to take it off, layering a shell or lighter puffy on top for the coldest descents.

Features: The pockets are perfect on this one, the chest pocket is super helpful for stashing a phone and the hand pockets are great for extra snack stashes and town. The hood fits great over a hat but not a ski helmet, which is expected on this one.
We loved this jacket for skinning in below zero temps. We never got sweaty and it is light, airy, comfy feel made it perfect for keeping on all day with only a shell or another light puffy worn over it for the descents. It is not, however, stretchy enough to be ideal for rock climbing in colder temps. Though it will work in a pinch, it’s a bit bulky and lacks the flexibility to fit well under a harness for cold rock cragging.

Outdoor Research

Deviator Hoody

Price: $229
Weight: 11.6 oz.
Fit: The trim fit is flattering and great for layering under other jackets.
Fabric: The shell fabric on this one is a bit loud and crunchy and lacks enough stretch to pull up the forearms while rock climbing. Fortunately, the fleece panels provide good stretch overall for climbing and great ventilation. The breathable insulation i.e., airy fleece, on the core is warm and comfy yet moves moisture well.  We found that the shell fabric over it however, is not as breathable as needed to keep the whole system dry when you overheat. It’s nice and wind resistant, but when worn under another shell for skinning in cold temps, it got steamy quickly.

Features: The center front zipper is way too light and separates from the get-go at the bottom. It feels like it will break at any time and leave you stranded with an open jacket. Though it looks sleek and lightweight, it feels like it cheapens the jacket overall and left us feeling vulnerable. We loved the fit and feel of this jacket, other than the tight sleeves, it was super comfortable on cold rock climbing and dry tooling days, just the right amount of warmth and stretch. It was also a great midlayer for ice climbing and cold ski touring days, though it was harder to regulate temperature as it did not seem to breathe or dry fast enough to keep it on all day under another layer.

Mountain Equipment

Switch Pro Hooded Jacket

Price: $299.95
Weight: 9.5 oz. 
Fit: We loved the contoured, close but stretchy fit of this jacket for both skiing and climbing. However, the cuffs could be a stitch more flexible for pulling up the forearm when climbing, and the hem width felt overly wide in the small size.  This would be fine if there was a drawcord adjustment to cinch it down but there is not, so any good breeze would flow up inside and quickly cool you down.
Fabric: The Octayarn insulation is light, airy and dries quickly. It feels super cozy warm when you first put it on but regulated heat extremely well. It’s easy to leave it on throughout your climb or activity without overheating or sweating up. The fleece panels are stretchy, great quality, breathe well, yet provide just the right amount of warmth for under another jacket or on its own.

The color blocking is a nice change from solids, but our women testers felt the blue/red combo was a little off and a bit too old school masculine. That said there are some other great options we loved for colors. Fabrics:   Overall, this easily becomes one you take on any adventure. Worn inside or out, it’s hard to even notice it as it fits and feels so comfortable throughout a wide range of temps and conditions while climbing, skiing, running, whatever your mountain pursuit.

Header photo courtesy of Irmeline de Sadeleer

Disclaimer of Liability: Technical rock and ice climbing is inherently dangerous. Neither Broad Beta, LLC., nor any of its employees, shall be held liable for any improper or incorrect use of the information described and/or contained herein, and Broad Beta, LLC. assumes no responsibility for anyone's use of the information.
Any person using our gear in any manner is personally responsible for learning the proper techniques and good judgment. We strongly recommend that every climber seek instruction by a qualified professional.

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