"What Our Gearhead® Experts Are Saying:""I wear the UPF 50+ Light Knee Sleeves on long summer rides when I want coverage without warmth. They breathe way better than you'd expect and stay in place thanks to the silicone grip. Once they’re on, I barely notice them—but I definitely notice not needing sunscreen.""When we need to keep our knees covered from the sun without adding bulk or heat, we pull on the Castelli UPF 50+ Light Knee 3 Sleeves. Designed for long, exposed rides and training sessions under cloudless skies, these sleeves deliver cooling performance with lightweight, breathable coverage. Solare fabric provides UPF 50+ protection while managing moisture efficiently, helping to keep us dry and comfortable on hot days. A silicone gripper at the top ensures they stay in place without slipping or bunching, even during intense efforts or shifting positions on the bike. Minimal in weight, but big on protection, these are our go-to for sunny endurance days."