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Hyperlite Mountain Gear 20 Degree Mummy Sleeping Bag vs Rab Mythic Ultra (20°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 Hyperlite Mountain Gear 20 Degree Mummy Sleeping Bag Rab Mythic Ultra (20°F)
Weight 703 g · 0.703 kg · 1.55 lb 700 g · 0.700 kg · 1.54 lb
Brand Hyperlite Mountain Gear Rab
Category Sleep System Sleep System
Hyperlite Mountain Gear 20 Degree Mummy Sleeping Bag
703 g

New-for-2026 ultralight mummy sleeping bag with 16.7 oz of 1000 fill power down in ultralight 7D nylon shell. Temperature rating 20°F (-6°C). Designed for cold-...

See it in your base weight → Full details →
Rab Mythic Ultra (20°F)
700 g

Winter-capable sleeping bag at 24.7 oz (700g) with 900-fill hydrophobic down, ideal for 3-season to winter transition camping.

See it in your base weight → Full details →

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Hyperlite Mountain Gear 20 Degree Mummy Sleeping Bag vs Rab Mythic Ultra (20°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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