Mountainsmith Whisp $250, 1lb 5oz, 30F
Summary: Do you own a digital scale, leave the toothbrush at home, and cut extra straps off your pack? Then the Mountainsmith Whisp could be for you. It was the lightest sleeping bag we tested, thanks to its superlight Dimension Polyant Airnet shell fabric and half-length zipper. The Wisp also impresses when it’s crammed into its lightweight stuff sack. It’s a battle, but the end result is a package the size of an average coconut. The Whisp also features open side baffles and a baffle on the lower half of its down-packed hood. The zipper doesn’t fall into the snag-free category, although it functions well when you’re mindful. Unfortunately, its starting point is not sewn closed, but configured like a jacket zipper, so the zipper body can lose contact with one of the tracks. The reconnecting process is easy, but an annoyance.
Pros: Lightest bag tested; extremely small stuff size
Cons: High maintenance half-length zipper; half-baffled hood
Overall grade: B
Mountainsmith: (800) 551-5889, www.mountainsmith.com

Super light sleeping bags

Test Results

Exped Sparrow
Feathered Friends Merlin
Marmot Hydrogen
Mont Bell Ultra Light Down Hugger #4
Moonstone 800 Lucid
Mountain Hardwear Phantom
Mountainsmith Whisp
Western Mountaineering UltraLite

Mountainsmith Whisp $250, 1lb 5oz, 30F
Summary: Do you own a digital scale, leave the toothbrush at home, and cut extra straps off your pack? Then the Mountainsmith Whisp could be for you. It was the lightest sleeping bag we tested, thanks to its superlight Dimension Polyant Airnet shell fabric and half-length zipper. The Wisp also impresses when it’s crammed into its lightweight stuff sack. It’s a battle, but the end result is a package the size of an average coconut. The Whisp also features open side baffles and a baffle on the lower half of its down-packed hood. The zipper doesn’t fall into the snag-free category, although it functions well when you’re mindful. Unfortunately, its starting point is not sewn closed, but configured like a jacket zipper, so the zipper body can lose contact with one of the tracks. The reconnecting process is easy, but an annoyance.
Pros: Lightest bag tested; extremely small stuff size
Cons: High maintenance half-length zipper; half-baffled hood
Overall grade: B
Mountainsmith: (800) 551-5889, www.mountainsmith.com

Super light sleeping bags

Test Results

Exped Sparrow
Feathered Friends Merlin
Marmot Hydrogen
Mont Bell Ultra Light Down Hugger #4
Moonstone 800 Lucid
Mountain Hardwear Phantom
Mountainsmith Whisp
Western Mountaineering UltraLite