Breathability
The Brooks-Range Mountaineering Alpha Softshell Jacket’s 10d exterior nylon shell and 20d nylon lining around the torso offers mid-level breathability, as does the softshell covered arms and hood. This amount of air permeability combined with the Polartec Alpha insulation around the torso, managed moisture and heat well for moderately aerobic activities in winter conditions near freezing.

Durability
The exterior fabrics of the Brooks-Range Mountaineering Alpha Softshell Jacket remain unscathed through two months of testing with continuous use under backpack straps and roaming amongst rocks. The sleeves are particularly robust, fending off sharp branches at speed while mountain biking. 

Weatherproofing
The Brooks-Range Mountaineering Alpha Softshell Jacket maintains core heat and fends off moderate winds, but it is noticeable that the arms are much colder than the torso, especially once activity has stopped. This sensation became apparent when the temperature neared 40F. A generously insulated main zipper backing aids in core heat retention. The DWR coating on both sleeves and torso beaded water in light precipitation only, with the sleeves resisting water penetration much better than the torso.  

Fit/Comfort
The Brooks Range Mountaineering Alpha Softshell Jacket’s cut finds a great compromise between being trim and sleek while still allowing layering underneath. The combination of tighter sleeve dimensions with stretchy softshell material and torso girth worked remarkably well with or without layering underneath or over the jacket. The interior of the jacket proved comfortable against bare skin or thin base layers. The aggressively asymmetric cuffs, sleek thumb slits and stretchy material gave the sleeves the best wrist and back of hand coverage of any jacket in this test regardless of how high the reach. The dual cord lock adjusted torso is a bit short to stay tucked into a harness during reaches. The Polartec Power Shield hood covers a climbing helmet but lacks a brim or adjustment and only stays on if the main zipper is closed up fairly high, but it is also thin enough to wear under the helmet. The main zipper has a substantial chin guard that worked great when burrowing down behind the collar.

Compressibility
The Brooks-Range Mountaineering Alpha Softshell Jacket can be crammed into a space that is slightly larger than a 1L water bottle. 

Features
The Brooks-Range Mountaineering Alpha Softshell has a basic set of features: two zipped handwarmer pockets (will not clear pack hip belts), a vertically oriented zipped chest pocket that easily fits a cell phone, and one interior stretch mesh dump pocket low on the torso.