Mountain Equipment Kinesis
Warmest fleece from the Fall/Winter 2018 Gear Guide.
If you want quilt-like weight but prefer traditional sleeping bag construction, you’ll need the lightest materials and most efficient shape. That’s what the Firefly has.
An armored shell protects this weather-resistant sleeping bag from all but the worst conditions.
It has the best warmth-to-weight ratio here; testers pushed it 10 degrees below its 23°F rating.