Patagonia Men's Nano Air Vest Light, yet durable 100% nylon ripstop shell and plain-weave liner offer generous mechanical stretch and exceptional breathability, with a DWR (durable water repellent) finish Revolutionary 60-g FullRange insulation warms and stretches; combined with the shell and liner, this creates a vest with excellent mechanical stretch and unprecedented air permeability (40CFM) Iconic Nano Puff brick quilting in the side panels improves shape and durability Center-front zipper has wicking interior storm flap and zipper garage at chin for next-to-skin comfort Shell: 1.3-oz 20-denier 100% nylon ripstop. Lining: 2-oz 50-denier 100% nylon plain weave. Both shell and lining with mechanical stretch and a DWR (durable water repellent) finish. Insulation: 60-g FullRange 100% polyester stretch insulation