Features: Integrated pad sleeve. Never roll off your pad again Rectangular shape offers more room in foot box and shoulders Cotton storage sack & nylon stuff sack included Built in pillow pocket holds a fleece or Big Agnes Pillow Interior fabric loops for sleeping bag liners 70" YKK #8 zipper. Mate together any of our left and right zip bags with a 70" zipper No-draft collar seals around neck to keep cold air from sneaking in. No-draft wedge insulates the connection between the bag and pad No-draft zipper tube insulates along the length of the zipper Shell fabric: Down proof, nylon microfiber rip-stop. WR surface treatment to repel water. Interior lining: Soft and breathable, down proof nylon microfiber with stain resistant finish. Pad sleeve: Nylon rip-stop. WR surface treatment to repel water. Construction: DualmaxTM: Blends synthetic insulation and goose down to yield a light weight bag with the optimum performance of both insulations. The Dualmax System places synthetic fill in a shingle construction on the outer layer to provide protection from the elements and the down fill on the inner layer to maximize user comfort. Synthetic Insulation: PrimaLoftTM eco: synthetic fill made from 50% recycled materials. Used in Dualmax construction.