The ultralight Rab Ascent 900 Sleeping Bag boasts an incredible warmth to weight ratio and protective features for ultralight backpackers and campers alike. Rab's proprietary Hydrophobic treatment protects the 650 fill duck down from moisture to keep you warm through rainy nights, and the windproof Pertex Microlight shell is surprisingly durable for how light it is. The bag's semi rectangular shape is roomier than standard mummy bags, and an angled footbox offers extra room so your feet don't feel squished. The Ascent also features an internal collar and a drawcord at the hood to seal out any cold drafts, and a zippered stash pocket that's perfect for headlamps. It comes with a full length zipper on either the right or left side, and a compression stuff sack for backpacking and a cotton storage sack to keep the bag prime for years.