The Backpacker Editor’s Choice Award Winning Sonic™ has been praised as the only bag you really need from -20 to 40 degrees. The premium suite of fabrics and 850 fill power down is complemented by adjustable Thermo Gills™, which regulate temperature without letting cold drafts in. It’s made for variable mountain climates.
Stretch construction at the knees offers extra room for side sleeping or to change positions during the night, as well maintaining the bag shape, thermal efficiency, and loft. An oversized draft collar with a Velcro closure seals in heat and keeps cold air out, and the waterproof/breathable footbox keeps your feet toasty and warm. This bag was made to keep you warm and comfortable in variable mountain climates.
