SealSkinz Thermal Waterproof Cap - AW15 100% Polyester With drop-down ear flaps and micro-fleece lining this the ultimate cap for cold weather adventures Totally waterproof, breathable and windproof Micro-fleece lining for warmth and moisture control Stiff peak, drop-down ear flaps & size adjuster for total comfort Material composition: Outer Shell: 100% Polyester; Micro-pourous Membrane; Inner: 100% Polyester