The Nemo Sonic Down Mummy Sleeping Bag is engineered for temperatures ranging from -20°F to 40°F, this Backpacker Editors’ Choice award-winning bag combines exceptional warmth with an eco-friendly design. Featuring next-generation Thermo Gill™ vents and a multistage zipper system, the Sonic allows you to fine-tune your comfort level with ease. Its chevron baffle construction prevents down migration, ensuring consistent loft and warmth. Made from 100% recycled, bluesign® approved fabrics and filled with 800 FP hydrophobic down certified by the Responsible Down Standard, this bag reflects years of field-tested improvements, including a redesigned draft collar and an innovative Toester™ footbox that keeps your feet warm and dry. Whether you’re in the backcountry or facing unpredictable weather, the Sonic sleeping bag is your go-to gear for extreme conditions, ensuring you stay comfortable and ready for whatever adventure lies ahead.