Neck guard that cuts out ultraviolet rays. It can also be used as a face guard if it is hooked on the ear hole. The front has a loose fit and is not too tight. When you use it as a neck guard, hang it on the neck. When you use it as a face guard, put the hole on the body on the ear. The back fits perfectly, and the nape of the neck, which tends to be ignored, is protected from ultraviolet rays. A loose ear hole that reduces stress on the ear. Because it uses chlorine resistant yarn, it prevents degradation even when used in pools or at sea. The more you sweat, the cooler it becomes! This is a measurement of the temperature of the skin contact surface using our metric. There is no guarantee of bodily sensation.