If you don't want a visor, but you really don't want a sunburn, the Giro SPF Ultralight Skullcap perfectly fits the bill. With a UPF30 rating, it blocks harmful UV rays. That's in addition to being light and airy perfect for keeping your head cool under your helmet. It's a one size affair, with an elastic rear panel to accommodate a range of head shapes and sizes. And since it's built from a blend of Power Mesh and antimicrobial X Static fabric, it'll stay fresh between washes. The Giro SPF Ultralight Skullcap is available in one size and in the color White.