Nemo Tensor Ultralight vs Sea to Summit Spark SP I

Weight and specs compared for 2026 — and which one to choose.

Nemo Tensor Ultralight is the lighter option — 57 g lighter than the Sea to Summit Spark SP I (14% less weight). If grams matter to you, that is the one to beat.

Spec	Nemo Tensor Ultralight	Sea to Summit Spark SP I
Weight	340 g · 0.340 kg · 0.75 lb	397 g · 0.397 kg · 0.88 lb
Brand	Nemo	Sea to Summit
Category	Sleep System	Sleep System

Nemo Tensor Ultralight

340 g

Ultralight inflatable pad with minimal noise. R-value 3.5.

Full details →

Sea to Summit Spark SP I

397 g

Ultralight 850-fill down sleeping bag rated to 25°C.

Full details →

Nemo Tensor Ultralight vs Sea to Summit Spark SP I: which should you buy?

If saving weight is your priority, the Nemo Tensor Ultralight wins — at 340 g it is 57 g (14%) lighter than the Sea to Summit Spark SP I (397 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.

More sleep system comparisons

Nemo Tensor Ultralight vs NEMO Equipment Tensor Elite Sleeping Pad Nemo Tensor Ultralight vs Therm-a-Rest NeoAir UberLite Nemo Tensor Ultralight vs NEMO Tensor Elite Ultralight Insulated Nemo Tensor Ultralight vs Zpacks Solo Quilt 20F Nemo Tensor Ultralight vs Zpacks Classic Sleeping Bag 20F Nemo Tensor Ultralight vs Therm-a-Rest NeoAir XLite NXT