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REI Co-op Magma 15 vs Western Mountaineering AlpinLite 20

Weight and specs compared for 2026 — and which one to choose.

No winner on weight yet. The recorded weights have not both been verified on the same basis. Size, included parts and single-item versus pair weights can differ. Check the linked sources before choosing a replacement.

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Spec REI Co-op Magma 15 Western Mountaineering AlpinLite 20
Weight 850 g · 0.850 kg · 1.87 lb 879 g · 0.879 kg · 1.94 lb
size 6'0" (180 cm), 20°F, total weight; 1 lb 15 oz omgerekend
Brand REI Co-op Western Mountaineering
Category Sleep System Sleep System
REI Co-op Magma 15
850 g

850-fill down sleeping bag rated to 15°F. Great value.

See it in your base weight → Full details →
Western Mountaineering AlpinLite 20
879 g

Roomy 20F mummy bag with 850+ goose down and continuous baffles, balancing warmth, comfort and low weight.

See it in your base weight → Full details →

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REI Co-op Magma 15 vs Western Mountaineering AlpinLite 20: which should you buy?

The listed weights alone are not enough to choose between these products. Confirm the size, included parts and weight basis against each source; choose equipment for the function and fit you need.

See where both rank against everything else in this category on the lightest sleep system page, or browse the full gear weight database.

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