50% polyester, 45% nylon, 5% spandex stretch fleece outer shell. * 100% polyester Dupont Thermolite® Active insulation. * Lined in a soft 78% polyester, 22% acrylic sherpa fleece that cups ears for a comfortable, snug fit. * Patented behind-the-head design fits comfortably over your ears while keeping your hairstyle intact. * Adjustable, click-to-fit frame fits varying head sizes.