The Big Agnes Greystone 30F sleeping bag delivers everything serious backpackers need for three-season adventures without the premium price tag. This lightweight mummy sleeping bag features 600 fill DownTek™ insulation that maintains its loft and warmth even when moisture tries to crash the party, while the PFAS-free water-repellent treatment keeps you dry without harmful forever chemicals. The traditional mummy shape and contoured hood work together to trap your body heat efficiently, making every gram count on the trail, while the smooth YKK two-way zipper lets you fine-tune ventilation from your toes up. Whether you're logging miles on remote trails or need a reliable backup for indoor adventures, this sustainable sleeping bag proves that eco-conscious gear doesn't mean compromising on performance when temperatures drop to 30°F/-1°C.