The SPF Ultralight Cap from Giro provides a bit of shade from the sun, with great sweat-wicking performance and an SPF rating of 30, so you can ride on summer days with a little extra skin protection. Designed to be worn under a helmet, it is thin enough to fit without bunching and light enough to practically disappear when you put it on. The Smart Seam construction keeps seams low and off most likely helmet contact points for reduced pressure and better overall comfort. The designers have also shortened the brim versus many other models of cycling caps for better upper peripheral vision when the rider is low on the hoods or fully down in the drops. X-STATIC, which is now also known as Ionic+, helps keep the piece fresher, reducing odor by fibers treated with silver for it's antimicrobial properties.