The Millet Men's Trilogy Insulated GTX Jacket handles anything that's cold and getting on towards vertical, so its the perfect jacket for fast alpine ascents, cold weather climbs, and serious ski mountaineering. Its Gore Tex Helios 2L membrane works with the fully taped seams to ensure waterproof protection that remains breathable, so sweat doesn't become an issue, and PrimaLoft Silver insulation adds enough warmth to keep you from freezing when you're on belay duty or picking your way up a wind blasted ridge. The Trilogy's alpine fit allows for easy layering both underneath and on top, and the stretch construction doesn't inhibit movement or expose your waist when you're swinging an axe or reaching overhead. It also features long zippers at each underarm for cooling airflow, and a powder skirt that's removable if you're planning on sticking to ice and rock. Millet designed the Trilogy's hood to interface smoothly with helmets and cinch down snugly around beanies, and decked the jacket out with water resistant zippers to offer additional protection. The hem seals up with an elastic drawcord and cuffs with hook and loop tabs, too, so you don't have to deal with spindrift blowing up your back and down your neck when you're trying to stay focused on not sliding down a 3,000 foot face.