Protect yourself from the sun and heat, with DE SOTO ARM COOLERS™. Yes, ARM COOLERS...contrary to what you wear in the winter to keep your arms warm, this set of sleeves keeps you cooler in hot weather. Skin Cooler ™ is a special moisture-radiating material that actually offers a cooling effect. They are guaranteed to keep your arms cooler in training and in racing than not wearing anything. If you do not find this to be true, return them for a complete refund! These sleeves block 75% of UVB rays, which is about as much as any bike jersey you may wear. We recommend you wear sunscreen underneath.