- high density weave 100% cotton twill - High density weave makes it highly windproof but soft and lightweight - Design based on the US Air Force MA-1 - Ribs on cuffs are seamless tubular knit with 2 layers of tension using wool - Lining is recycled polyester ripstop - Fill is highly thermal and lightweight PRIMALOFT® Black Insulation - Oversized silhouette around the shoulder and body width