Big Agnes Lost Ranger 3N1 0°

The Big Agnes Lost Ranger 3N1 0° is a modular winter system made of two separate pieces — an inner mummy bag and an outer quilt-style shell — usable independently in milder conditions or combined for a full -18 °C limit rating (comfort -11 °C). The 650-fill hydrophobic down weighs 840 g; at a combined system weight of 1698 g that works out to 94.3 g per degree, a solid figure for a two-piece system rather than a single bag. A zipper on both sides eases entry and venting, shell and liner are recycled 20D polyester, and the whole system is PFC-free. An insulated collar and draft tube handle seam insulation, and pad loops anchor the bag to a sleeping pad. The manufacturer backs it with a two-year warranty. The modularity suits users who want one system covering multiple seasons — the outer piece alone for shoulder-season trips, both combined for winter expeditions. Unlike some other Big Agnes bags, this one is not coupleable with a second unit.