A heavyweight merino base layer top designed to help regulate temperature during high-intensity activity, the 260 ZoneKnit Long Sleeve Crewe features 100% pure and natural merino wool. Icebreaker Mens ZoneKnit 260 LS Crewe Features: ZoneKnit - Engineered body mapped technologyto regulate your body temperature andlet your skin breathe during high-intensity activity Thumb slits keep your sleeves in place and hands warm Raglan sleeve construction for mobility Gusseted underarms for mobility and comfort Flatlock seams to prevent friction Drop tail hem for added coverage 100% Merino Wool