Product Description Made from a luxurious blend of 90% nylon and 10% spandex, these sleeves offer a breathable, second-skin fit that keeps you cool and comfortable. Our top-of-the-line UPF 50+ sleeves provide superior protection against harmful UVA and UVB rays, perfect for all your outdoor activities and available in a range of stylish colors. COOLING & UPF 50: With the newest UPF 50 protective technology, baseball arm sleeves block out over 99% of harmful sun rays to offer your arms an all-around sun protection. HIGH ELASTICITY & BREATHABILITY: The Cycling sleeves are made of breathable and elastic materials, the quick-drying fabric of the arm covers can keep your arms cool during exercise. SEAMLESS & COMFORT: Our premium arm covers offer comfortable wearing experience all the time. Cooling arm sleeves are seamless and offer perfect 360° fit. And the sleeve will not leave marks on the arm. ONE SIZE FITS MOST: Our arm cover sleeves are stretchable enough to ensure stretchy fit for most men and women, and durable enough to guard against light levels of abrasions. PRODUCT & SERVICE: You can buy with confidence. And if you are not satisfied with it or you have any question, please feel free to contact our customer service, we will give you a satisfactory solution within 24 hours.