Sea to Summit Ember XT 0°C Sleeping Bag vs Therm-a-Rest Hyperion 20F/-6C (Regular)
Weight and specs compared for 2026 — and which one to choose.
Ultralight 0°C rated bag with 850+ UltraDry Down insulation. Stretch-knit lining and sculpted hood for packability and comfort.
Full details →Ultralight 20F down mummy bag with 900-fill Nikwax Hydrophobic Down for fast-and-light backpacking.
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Sea to Summit Ember XT 0°C Sleeping Bag vs Therm-a-Rest Hyperion 20F/-6C (Regular): which should you buy?
If saving weight is your priority, the Therm-a-Rest Hyperion 20F/-6C (Regular) wins — at 567 g it is 42 g (7%) lighter than the Sea to Summit Ember XT 0°C Sleeping Bag (609 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.