For winter hiking, skiing, & cold days of all kinds, the icebreaker Men's 260 Tech Long Sleeve Crew is a fantastic base layer. Made with 100% Merino wool in icebreaker’s mid-weight category, it naturally regulates body temperature & resists odours, so you can wear it more & wash it less. The slim fit, combined with the friction-free flatlock seams, makes it easy & comfortable to layer under other pieces. Offset shoulder seams also mean increased comfort when wearing a pack, while gusseted underarms ensure arms-up mobility.