The Chill-Its 6632 Cooling Skull Cap is a low-profile cap that wicks away moisture when worn dry and provides evaporative cooling relief when worn wet. Designed with stretchy performance knit fabric to provide UPF 50+ sun protection against harmful UV rays. An elastic band lines the interior for a snug and comfortable fit. In order to activate, just soak in water until saturated, then wring out excess water the evaporative cooling process begins instantly and lasts for hours. If wearing dry, the moisture-wicking fabric draws perspiration away to help keep you dry. Anti-odor treatment keeps this cooling headwear fresh, while reflective accents ensure workers are seen in low-light conditions. The low-profile design fits comfortably under a hard hat or helmet and is great for construction workers, landscaping, roofing, or anybody working in the heat. It can also be used to reduce the risk of heat stress while mountain biking, motorcycling, gardening, hiking, playing sports and more.