Traditionally, inner and outer layers of fabric are stitched together and then quilted with additional stitching. But this jacket is made with a single sheet of fabric that's folded over and woven together in discontinuous channels to hold the down. This cutting-edge technique saves weight, maximizes breathability, helps reduce cold spots, and minimizes down migration.The two-way stretch shell provides exceptional mobility and features a super-durable water-repellent finish that beads moisture. High-loft Premium Down insulation delivers sub-zero warmth in mere ounces.