Redesigned tip attachment

5mm double-lined neoprene

Hook-and-loop strap closure

KEY-TECH FLEX contoured underfoot support for lasting comfort

Deep center lugs aggressively claw into unconsolidated snow for extreme acceleration and braking traction

Sonic Cold Weather Sleeping Bag steps Redesigned tip attachmentSonic is built to be the only bag you need from 20F to 40F. The Backpacker Editors Choice award winning big mountain bag offers exceptional warmth and tuneability with a reduced environmental impact. This bag features our next generation Thermo Gill vents, with a new multistage zipper system that dramatically increases the usable temperature range of the bag and allows fine tuning of comfort from within. Sonics chevron baffle construction better