Therm-a-Rest Vesper 45

Lightest sleeping bag

Brand: Therm-a-Rest

Model: Vesper 45

Our take There are grapefruits larger than the packed size of this ultralight quilt. “I got everything I needed for a four-day mountaineering mission on California’s 13,150-foot Mt. Ritter into a 35-liter pack, thanks in large part to this quilt’s tiny packed size,” one tester says. Credit the 900-fill goose down, 10-denier nylon, and lack of zippers. Despite the wispy weight, there are still a few features: A snap affixes the top of the quilt around your neck like a scarf (the button closure stays put once snapped, but it’s not adjustable and can feel restrictive around larger necks) and 4-inch-wide side baffles drape over the side of your pad to seal in heat. We slept warm down to 35°F in California’s Ansel Adams Wilderness.

The details Three removeable elastic bands wrap loosely underneath the sleeping pad to keep the Vesper in place; we thought they were silly until we saw a 15-degree shift in comfortable sleeping temps when we didn’t use them. Also, the footbox is roomy and tall enough for size 12 feet.

$280; 12 oz.; 45°F; regular and long

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