The name can be misleading this jersey started life as a lightweight jersey to make climbing easier but it turned out to be ideal for hot weather and surprisingly its very good in cool weather or even rain under a vest or jacket because it has absolutely minimal moisture absorption the inner lining keeps it modest and adds a nice desgin detail to one of our most technical jerseys ever features stradapro 3d fabric on back provides support to pockets and upf 16 protection 75 gm2 flus