VERSATILE BASELAYERThis performance half-zip is the perfect first layer in winter, or a stand-alone in spring or fall. Unzip the collar for cooling.WARM AND DRYOur thermal-reflective lining holds heat in, while the wicking fabric keeps you from getting a chill.PERFORMANCE FITThe ergonomic, body-contouring seaming is made to move, and thumbholes keep the sleeves in place.Omni-Heat™ thermal reflectiveOmni-Wick™4-way comfort stretchAntimicrobial treatment protects this product from bacterial growthErgonomic seamingFlatlocked constructionThumb holes