Sonic Down Mummy Sleeping Bag brand-The Mountain Air The spring steel perimeter rod

The spring steel perimeter rod works in tandem with a PE board cone to disperse weight effectively and also allows for secure anchor points for the shoulder straps to attach to

The welded build and waterproof zippers keep dry gear dry or can be used to isolate wet clothes

Charge multiple devices at once

giving you the perfect hang

The IPX4 ingress protection rating means this is engineered to keep up in the field

Sonic Down Mummy Sleeping Bag brand-The Mountain Air The spring steel perimeter rodBuilt to be the only bag you need from 0F to 40F, weve updated our Backpacker Editors Choice award winning big mountain bag, Sonic, for even greater warmth, tuneability, and reduced environmental impact. With this bag, we are launching our next generation Thermo Gills with a new multi stage zipper system that dramatically increases the usable temperature range of the bag and allows fine tuning of comfort from within the bag. Sonics new chevron baffle