Being cold makes it just about impossible to do anything else, whether its tying your shoes or making good decisions, so staying warm is seriously important when you're on alpine expeditions or frigid climbs. Mammut packed the Ambler Pro IS Men's Hooded Jacket full of 750 fill goose down to lock in heat and seal out cold, and constructed it from water resistance Pertex Endurance fabric to keep moisture from turning the insulation clumpy and cold. In high wear areas like the shoulders, arms, and waist, Mammut also laminated the fabric to a DryTech 2L waterproof and breathable membrane, so you'll have extra protection when you're climbing through a snow storm or swinging your way up frozen falls. Mammut didn't overload the Ambler with features, but it included enough pockets, cinches, and flaps to take care of all your alpine needs. Hand, chest, and internal pockets keep key gear like food, maps, and gloves safe, while a drawcord hem, internal cuffs, and a zipper covering storm flap provide full protection from wind and spindrift. The down filled hood is easily removable if you're looking to travel light, and the included stuff sack makes the Ambler easy to pack and carry when it's not keeping you warm.