Evaporative Cooling Headwear, which includes many styles (e.g., baseball, bucket, beanie, sombrero, triangle, visor, bandana, skull cap, headband) or interior inserts, can reportedly provide up to 20º cooling relief for as long as 2 hours. Most of these products are activated by dipping them in cold water to activate targeted cooling zones. According to the manufacturers, the machine-washable fabrics from which the products are made are usually chemical-free, provide UPF-50 sun protection that blocks UV rays, and have breathable panels for maximum airflow.