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Cumulus Aerial 250 vs Rab Mythic Ultra 180 (32°F)

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 Cumulus Aerial 250 Rab Mythic Ultra 180 (32°F)
Weight 385 g · 0.385 kg · 0.85 lb 400 g · 0.400 kg · 0.88 lb
Brand Cumulus Rab
Category Sleep System Sleep System
Cumulus Aerial 250
385 g

Ultralight down sleeping bag with 900 FP goose down, single-layer design with no zipper, perfect for thru-hiking and backpacking.

See it in your base weight → Full details →
Rab Mythic Ultra 180 (32°F)
400 g

Ultra-lightweight 3-season sleeping bag weighing just 14.1 oz (400g) with 900-fill hydrophobic goose down and titanium technology.

See it in your base weight → Full details →

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Cumulus Aerial 250 vs Rab Mythic Ultra 180 (32°F): 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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