Western Mountaineering TerraLite

The TerraLite is built for side sleepers and anyone who finds standard mummy bags too confining: a wide semi-rectangular cut with 850+ fill-power goose down, dual full-length YKK zippers on both sides, and a floor width generous enough (footbox 104 cm, shoulder 165 cm) to allow real inside movement. Unlike most of Western Mountaineering's range, it carries EN ISO 23537 lab-tested ratings rather than only a manufacturer estimate: comfort -2°C, limit -8°C, extreme -26°C — giving a clearer, independently verified picture of its warmth. At 765 g with 455 g of fill, its warmth-to-weight figures are among the strongest in the brand's line, helped by the 12D nylon ripstop shell, 15D nylon taffeta liner and DWR treatment. Zippers on both sides plus coupling compatibility mean two TerraLites can be joined into a double bag. The combination of wide cut, dual zippers, and tested cold-weather rating makes it a strong three-season choice for hikers who move in their sleep, at a modest weight penalty over the brand's narrower mummy bags.