The XKG Beanie is the warmest hat in the XKG Series. Built with an outer layer of stretch fabric and inner high pile fleece lining, this windproof and water resistant hat will keep you comfortable when the conditions get tough. 95% Polyester 5% Spandex Outer Fabric Windproof & Water Resistant High Pile Fleece Lining Polygiene Odor Control Treatment Side Stretch Panels DWR Treatment Product Weight: 1.9 oz.