HITOP Outdoor Sports Black Thermal Cycling Skull Cap Helmet Liner, One Size 90% Polyester, 10% spandex fleece. Soft fleece inside provides long lasting warmth and comfort. Stretchy, breathable fabric wick sweats away. Windproof, snow proof, breathable, dry-fast and warm. Suitable for outdoor activities. Such as ski, climbing, biking, hiking and camping etc. For unisex. One size fits most.