Western Mountaineering AstraLite vs Zpacks Classic Sleeping Bag 20F
Weight and specs compared for 2026 — and which one to choose.
Ultralight 3-season sleeping bag with 850fp down and 12D shell. Designed for fast-and-light alpine pursuits and long trail journeys.
Check price Full details →Mummy-style sleeping bag rated to 20F (-7C) with 900-fill goose down. DCF outer shell for low weight and packability. Water-resistant treatment included.
Check price Full details →Western Mountaineering AstraLite vs Zpacks Classic Sleeping Bag 20F: which should you buy?
If saving weight is your priority, the Zpacks Classic Sleeping Bag 20F wins — at 347 g it is 149 g (30%) lighter than the Western Mountaineering AstraLite (496 g). That said, the heavier option may justify the extra grams with more capacity, durability or comfort, so weigh the trade-off against how you'll use it.
See where both rank against everything else in this category on the lightest sleep system page, or browse the full gear weight database.