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Feathered Friends Swallow YF 20°F vs Sea to Summit Spark SP III

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 Feathered Friends Swallow YF 20°F Sea to Summit Spark SP III
Weight 828 g · 0.828 kg · 1.83 lb
size Regular, average weight 20°F
 709 g · 0.709 kg · 1.56 lb
Brand Feathered Friends Sea to Summit
Category Sleep System Sleep System
Feathered Friends Swallow YF 20°F
828 g

Premium 950-fill down sleeping bag rated to 20°F.

See it in your base weight → Full details →
Sea to Summit Spark SP III
709 g

850-fill down sleeping bag rated to 0°C / 32°F.

See it in your base weight → Full details →

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Feathered Friends Swallow YF 20°F vs Sea to Summit Spark SP III: 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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