When progressing higher and further at alpine altitudes and above staying warm and dry is vital. That's where the active insulation layer comes in. Ventrix™ dynamic venting insulation means the Summit L3 delivers both warmth and efficient moisture management. Extra insulation over the body - where you need it most - and less on the sleeves, together with perforations over the spine help prevent overheating. And when you do work up a sweat, FlashDry-XD™ technology efficiently wicks it away. A durable water repellent prevents wetting-out if you get caught out by the weather. The L3 features a pre-tensioned, helmet-compatible hood, stretch-knit cuffs and side-cinch hem to keep chilling winds at bay. It's also built to withstand brushes with rock thanks to the durable nylon ripstop weave. Stretch, the cut itself and underarm gussets ensure full climbing mobility. And seamless shoulders reduce the chance of chaffing and discomfort when carrying a heavy approach backpack. Wear it while you belay, while you climb and while you repel. Summit Series layers all work together for optimum performance in terms of breathability, insulation, weather resistance and moisture management.