Nylon, Spandex UPF 50 Protection: Arm Covers Made of Premium Soft Fabric, 70% Nylon and 30% Spandex. It blocks up to 97% of harmful UVA and UVB rays, preventing sunburn and skin aging. No more sunscreen. You have maximum UV protection throughout the day. Cool Feeling: Extremely stretchy material cooling arm covers are cooler than bare skin. Keeps you cool on hot summer days. When you put the sleeve on, it goes straight down 5 degrees. Don't worry about being exposed to the hot sun. Comfortable and Breathable: The high-performance fabric wicks sweat and dries quickly, ensuring excellent comfort and keeping your skin fresh all day long. Anti-slip elastics on the top and bottom ensure the sleeves don't slip off your arms. Best Arm Cuffs fit most people's arms without any pressure or discomfort. Seamless Design: The cooling arm cover is seamless and elastic. It provides a perfect 360 fit. Our elastic sleeves are sure to stay on your biceps without itching and leaving marks on your arms. The V-knitting process fits the curve of the arm and helps the arm to release pressure better. FITS YOUR ACTIVITIES: Arm Covers are designed for prolonged, high temperature use in the sun, whether you're running, golfing, fishing, basketball, biking, hiking, driving or gardening, our lightweight arm covers Both keep you comfortable. Also suitable for indoor events and even your workplace. Your arms won't stick to your desk. You can rest assured that you are protected all day long during any outdoor activity.