The Triple8 Certified Sweatsaver Helmet was designed to offer everything you could ever want and need from a helmet, comfort, protection, impact absorption and sweat wicking it does it all. The first and only helmet to fully integrate the best of high impact absorbing EPS foam with thick dual-density foam and plush sweatsaver fabric. This helmet comes with two sets of liners so you can get the perfect fit with either the thinner or thicker set. The Triple8 Certified Sweatsaver Helmet complies with CE 1078, U.S. CPSC Safety Standard for Persons Age 5 and Older and ASTM F-1492 Skate safety standards. Size guide: X-Small/Small: 20" - 21.25" (51 -54cm) Small/Medium: 21" - 22.5" (53 - 57cm) Large/X-Large: 22.5" - 23.5" (57 - 60cm)