Rab Mythic Ultra 180 (32°F) vs Rab Mythic Ultra 20
Weight and specs compared for 2026 — and which one to choose.
Ultra-lightweight 3-season sleeping bag weighing just 14.1 oz (400g) with 900-fill hydrophobic goose down and titanium technology.
20-degree sleeping bag weighing 440g. Features TILT lining technology that reflects heat back to achieve superior warmth-to-weight ratio.
Building a pack? Add either one to your HikeLoad list, or drop its weight into the base weight calculator, and see what it does to your total weight.
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Rab Mythic Ultra 180 (32°F) vs Rab Mythic Ultra 20: which should you buy?
If saving weight is your priority, the Rab Mythic Ultra 180 (32°F) wins — at 400 g it is 40 g (9%) lighter than the Rab Mythic Ultra 20 (440 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.