The Navajo uses 650 Goose Down insulation. The slant baffle construction gives you a warm bag rated at 20 or 0 degrees and it naturally breathes for added comfort. This is our lightest and most compressible mummy bag. A contoured hood, a self repairing #8 YKK zipper, and a 300T round ripstop outer give you the features you need in a good backpacking mummy bag. A compression stuff sack is included along with a gray storage stuff sack.