Choose this silky base layer from PolarMAX for layering beneath insualtion and outer shell when performing highly aerobic activities in colder weather to regulate moisture and temperature so you stay more comfortable for longer!FEATURES: Poyester Knit Fabric: Wicking Quick Drying Breathable Lightweight Comfy!Acclimate FabricAcclimate fabric is exclusively featured in all PolarMAX fabrics. Acclimate rapidly pulls or `wicks` moisture away from the skin to the fabric`s outer surface for quick evaporation which means you stay drier warmer and more comfortable.