With its timeless design and unique rubber finish, Triple 8's Sweatsaver Liner Skateboarding Helmet is a classic, offering comfort and safety for skateboarding, roller skating, and roller derby. The design incorporates an ABS outer shell with a stink-free, moisture-wicking Sweatsaver liner inside. Adjustable chin strap ensures a comfortable fit. Terrycloth liner is easily-removable for cleaning; wash gently by hand and air dry. The Triple Eight Sweatsaver Helmet is available in five sizes to fit kids, youth, and adults: X-Small fits 20.1Ð20.5 in (51Ð52 cm), Small fits 20.6Ð21.3 in (52Ð54 cm), Medium fits 21.4Ð22 in (54Ð56 cm), Large fits 22.1Ð22.9 in (56Ð58 cm), X-Large fits 23Ð24 in (58Ð61 cm). To determine proper size, measure with a soft tape measure or string. ManufacturerÕs 180-day limited warranty.