The Frostline Hat is built for ultimate winter weather protection. Water-resistant, ultralight 30D Pertex Endurance fabric keeps out the elements, while Posh Pile fleece provides warm, wicking insulation. 1/2 zip-out face mask and fleece-lined earflaps provide adjustable protection from biting wind and snow, and the foam brim snaps up for greater visibility when you're eyeballing the route ahead.