【COOL FEELING】: Extremely elastic material cooling arm sleeves cooler than bare skin. Keep you feel cool in the hot summer. When you wear the sleeve, it will straight down 5 degrees. No worry be exposed to blazing sun.【UPF 50 PROTECTION】: The arm sleeve is made of premium soft fabrics, 70% Nylon and 30% Spandex. It can block out as high as 97% of harmful UVA and UVB rays to prevent sunburn, skin aging. No more Sunscreen. You are maximum UV protected all day long.【SEAMLESS DESIGN】: The cooling arm sleeves are seamless and elastic. Our stretch fit sleeves surely can be stayed on your bicep, not make you itchy and leave imprints on your arms. V-type knitting process fits to the arm curve, helping the arm to release the pressure better.