What Our Gearhead(R) Experts Are Saying: "I like this bag for cold-weather trips where pack weight still matters. The DownTek insulation stays lofty even in damp conditions, the draft collar actually seals in heat, and the mummy cut keeps warmth efficient without feeling overly restrictive. It's a solid balance of warmth, compressibility, and value." We reach for the Greystone Sleeping Bag 0 Down when nights dip low and dependable warmth matters most. Big Agnes built this bag to deliver cold-weather performance without unnecessary bulk, making it a reliable choice for backpacking trips, car camping adventures, and anywhere else a warm night's sleep is non-negotiable. The traditional mummy shape keeps heat close while staying comfortable enough for extended use. Inside, 600 fill DownTek(TM) insulation provides excellent warmth-to-weight performance while resisting moisture in variable conditions. Recycled shell and lining fabrics add durability and a softer hand feel, and the water-repellent finish helps keep condensation and dampness at bay. Thoughtful details like the contoured hood, oversized draft collar, and anti-snag zipper work together to seal out the cold, so we stay warm and rested when it matters most.