Our Armycrew 3M Thinsulate Insulation Fleece Lined Long Cuff Ribbed Beanie is a perfect winter outdoor beanie hat tat will keep your head in warmth from cold elements. Great for snowboarding, skiing, snow trips, camping and others. Made of 100% Acrylic. 3M Thinsulate Insulation. Fleece lined inside for extra warmth. Thick, warm and soft material. Easily stretchable. Ensures a comfortable fit for most head types. One size fits most.