Securefit Pressure Diffusion Technology: Flexes and self-adjusts to the size of the wearer's head. Reduces pressure and increases comfort for all day wear. Fits head sizes from 6-1/4 to 8 (50-64 cm) Optimized Comfort: With 2 levels of height adjustment. Contains a premium washable and replaceable sweatband that is made of moisture-wicking material designed to help keep workers cool and dry 3M Uvicator Sensor: A visual cue when it's time to replace the hard hat due to UV exposure Protection And Comfort: H-Series non-vented hats meet ANSI/ISEA Z89.1 Type 1, Class G and E requirements Compatible: With cap-attached 3M hearing protection, communication products and other accessories DOSH SIRIM Approved