Capilene® hits the sweet spot between weight, breathability and wicking performance so you can wear this top alone or under layers to stay dry and comfortable Smooth face allows easy layering; internal diamond-grid pattern rests lightly on the skin to trap warmth Forgiving stretch moves with you; full underarm gussets provide unhindered shoulder mobility Hollow-core yarn construction increases wicking performance and speeds dry times HeiQ Fresh durable odor control means less washing and more wearing Flatlock seams and rib-knit collar with internal neck tape for chafe-free comfort; raglan shoulder seams and offset side seams lie smoothly beneath pack straps Elastic thumbholes add coverage for your hands and ease layering Droptail hem extends coverage Fair Trade Certified™ sewn