The Marmot Zeus vest is a great way to stock up on warmth without bulking up your pack or your layers.

• Water-resistant, ultralight downproof ripstop shell surrounds premium 800-fill-power goose down; Durable Water Resistant finish repels moisture and stains
• Draft flap behind front zipper keeps breezes out; chin guard protects from abrasion
• Features a drawcord hem and zippered handwarmer pockets; left pocket doubles as a stuff sack