Designed to cut weight without compromising your comfort, the Rab Neutrino Sleeping Bag family is tailor-made for mountaineers, climbers, and fast-and-light backpackers. Available in multiple weights to suit environments from the chilly to the truly frigid, these bags are packed with hydrophobic-treated 800-fill-power European goose down that’s certified cruelty-free, according to the Responsible Down Standard (RDS). Combined with the lightweight, recycled Pertex Quantum fabric, these bags are both ultralight and ultra compressible for easy packing when space and weight are at a premium. And whether you’re sleeping on a portaledge, in a mountain hut, or enjoying the comfort of your tent, the tapered mummy cut keeps these bags close to your body for maximum heat retention.