Sea to Summit Spark Pro Down Sleeping Bag vs Zenbivy Ultralight Bed
Weight and specs compared for 2026 — and which one to choose.
Ultralight down sleeping bag at 765g with 900+ fillpower RDS-certified down, 15°F rating and Free-Flow Zip system for versatility.
Check price Full details →Hybrid sleep system: a 482g down quilt plus an 85g fitted sheet that attaches to a sleeping pad for a traditional, draft-free bed-like sleeping experience.
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Sea to Summit Spark Pro Down Sleeping Bag vs Zenbivy Ultralight Bed: which should you buy?
If saving weight is your priority, the Zenbivy Ultralight Bed wins — at 567 g it is 198 g (26%) lighter than the Sea to Summit Spark Pro Down Sleeping Bag (765 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.