Features of the Pearl Izumi Sun Sleeves Arm Warmer In-R-Cool Technology to provide optimal skin-cooling effect and moisture management when you perspire Black colorway Features Elite Transfer fabric with In-R-Cool powered by coldblack Technology to provide optimal cooling UPF 50+ sun protection by reflecting UV rays White colorway Features Elite Transfer fabric with UPF 50+ Sun Protection and Ice-fil Reflective elements for low-light visibility