Weighing next to nothing and packing down small, the Sea to Summit Traveller TrI is a great warm weather bag, year round indoor bag, or travel companion for use in hostels, huts, or hotels. . Lightly tapered rectangular cut decreases weight and bulk without sacrificing comfort or reducing overall blanket size bag unzips completely for use as a reversible comforter. 750 Fill Power Premium European duck down is a high quality insulation treated with ULTRA DRY Down ULTRA DRY Down treatment is a permanent nano level water repellent polymer that vastly improves the down's reaction to water without affecting its weight or loft performance ULTRA DRY also inhibits bacterial and microbial growth, making the bag more hygienic and long lasting Treated down retains over 60% more loft, absorbs 30% less moisture, and dries 60% faster compared to untreated down. UL 15D nylon fabric used for the shell and inner face is lightweight and durable. Drawstring closures at the foot and collar provide lightweight and comfortable climate control. YKK 3 zipper opens the bag fully for use as a blanket or to zip together with another TrI bag. Super high density 210D polyester cloth hidden in the draft tube is exceptionally stiff and eliminates zipper snagging. Includes lightweight Ultra Sil compression bag, mesh storage cell, and large cotton laundry bag.