The Mens Prana Asylum Shirt is how Prana does flannel. Made from 100% Organic Cotton, the Asylum Button Down is soft, warm, and breathable. This Prana flannel features a thermal-lined waffle interior to trap heat for extra warmth. Other features include antique metal ringsnaps on the front placket, flap pockets, and cuffs. The Mens Prana Asylum Shirt offers easy warmth on cold days.