The reasons for slipping on Giro's Chrono UV Arm Sleeves before a ride are as numerous as the skin cells they cover up. Being a cyclist entails spending an inordinate amount of time in the sun, with training sessions, century rides, and races routinely extending our exposure from five to 10 hours at a time. We owe it to our skin and our future health to alleviate the potential for damage, and the Chrono UV Arm Sleeves provide UPF 50+ protection to reduce the harmful UV rays hitting our skin. ,p>While they're not as light and airy as riding with bare arms, they're still light enough for all conditions but the most sweltering summer days, and their high-stretch synthetic material and spiral knit construction efficiently wicks moisture, keeping you free from soggy slop and the sun's punishment simultaneously.