High-Density Polyethylene (HDPE) shell designed for strength. Extended back brim helps protect neck and ears from the sun's UV (ultraviolet) rays， as well as a run-off for rain and snow. 4-point suspension with 3-dimensional height adjustment. Wheel Ratchet is easy to use and creates a firm comfortable fit. Premium moisture managing sweatband. Universal accessory slots accepts virtually any competitors' accessories. Meets ANSI/ISEA Z89.1，Class E / CSA Z94.1-05， Type 1 requirements. One size fits most.