The XKG Summit 0 Degree Mummy Bag is our warmest high-performing sleeping bag. This super lightweight bag has a carry weight under 4 pounds and built to keep you warm and comfortable during the cold nights in the backcountry. Over-sized 84" x 32" Thermolite Insulation - 2.9 lbs. fill Drawstring Closure 20D 380T Poly Liner Chest & Shoulder Baffle Full Length YKK Zipper Lightweight Carry Weight - 3.75 lbs. External Chest Pocket 20D Poly Ripstop Shell Lightweight Compression Bag Prop 65 WARNING for California