The R1 Air knit paneling under the arms really does dump heat when I'm moving fast, but my core stayed warm on a windy ridge. Weighs almost nothing packed in my running vest.
Violet M.★★★★★
I run hot on climbs so I usually strip layers fast, but the R1 Air knit paneling on this actually breathes instead of trapping sweat. The 40-g FullRange insulation keeps me warm on the cold starts without turning into a sauna once I get moving.
Richard★★★★★
Wore this on a windy ridge hike and the 40-g FullRange insulation kept me warm without overheating on the climb. The R1 Air knit panels dump heat exactly where I need it, and it packs down small enough to stuff in my pack.