Weathershedding
This 2.5-layer Pertex Shield+ jacket comes with fully taped seams and a durable, ripstop nylon exterior. It’s designed more as lightweight emergency rain protection than as a jacket for sustained running in downpours. The fabric does an excellent job beading up water but eventually moisture can begin to seep through. The hood features a slightly stiffened brim and rear drawcord adjustment; testers found it to stay reasonably put while running, though with time, some rain dribbled in around the neck. No adjustability at the wrists left them vulnerable as well to rain seepage.

Breathability
As a multi-sport jacket geared, perhaps, more toward climbers than trail runners, it wasn’t the most breathable design for truly aerobic efforts. Given the lack of pit zips or venting, the fabric itself breathed quite well—an improvement the original Helium Jacket. Testers experienced very little internal moisture buildup, even in warm weather.

Function
Outdoor Research has stripped this piece down to the essentials, so there aren’t many bells and whistles to speak of. A single zippered chest pocket is large enough to stow a phone and offers decent waterproof protection. Otherwise, there are no hand pockets. The cuffs feature a short stretch of elastic, but otherwise are loose and non-adjustable, which seemed like a strange oversight on the part of the product designers.

Fit/Comfort
Other than the non-adjustable aspects of the jacket’s fit, it has a nice, natural athletic cut. Note that it does run snug, so size up to accommodate layers.

Packability
This weighed in about average—several ounces heavier than the lightest jacket tested (from Berghaus), but several ounces lighter than quite a few other offerings from Patagonia, Mountain Hardwear, Montbell and Eider. Its thin, flexy material packs down very easily into its own integrated stash pocket.