Our ultra-warm down parka for shiver-free belays on ice and alpine routes, après-trek warmth at Everest Base Camp, and anytime you take a break in bone-chilling temps. High-lofting RDS certified 800-fill down in a 3-D box baffle construction stops any and all cold spots while durable materials throughout ensures its outer layer status—abrasion-resistant Pertex on the outside, sure, but also down to the tough diamond-shaped yarns. And on days when the bivy and steep pitches are on the itinerary, pack it way with perfect convenience.