The Rain Walker Rain Hat: The perfect Rain Walker to keep your head dry during the spring/fall/winter rainfalls! This large brimmed hat is made from Dintex, a 3 layer polyurethane fabric that protects against wind and rain while allowing breathability and comfort. The hat is available in four sizes with an adjustable slide buckle at center back that allows for size variations. The small, medium, and large range will fit most heads. To determine your size, measure the circumference of your head just above the ears and across the middle of the forehead. Match the measurement to the corresponding size as listed. If in doubt buy the size larger. Each size allows one inch wearing ease. Outer shell: 94%polyester, 6% spandex Inner membrane: Polyurethane