Skins Essentials Compression Arm Sleeves 76% Nylon/24% Spandex Imported UPF 50+ UV protection and chafe free flat lock stitching World's first Dynamic Gradient Compression delivers more oxygen-filled blood to active muscles, increasing endurance, power, and efficiency SKINS gradient compression delivers more oxygen filled blood to arm muscles to increase power and stamina Designed to minimize pooling in the forearms SKINS Performance Compression: It's equipment, not clothing