Lightweight DH certified helmet M-Forge Carbon shell with composite chin bar, in two shell sizes Maximized ventilation with 22 vents Removable mouthpiece ventilation cover DD ring closure system 360° Turbine Technology Reduced peak brain acceleration by up to 30% at impact speeds associated with concussion Dri-Lex® moisture wicking, breathable, anti-odor and washable inner liner Optimal neck brace compatibility Visor with breakaway function for rotational reduction in a crash In-molded EPS + EPO impact foam for superior energy absorption Weight: Estimated from 750 +/- 50g (1.65 lbs)Certified and tested: AS/NZS 2063:2008, ASTM F1952–15, EN1078, CPSC 1203 Sizing #S (55-56cm – 21 5⁄8 - 22) #M (57-58cm – 22 ½ - 22 ¾) #L (59-60cm – 23 ¼ - 23 5⁄8) #XL (61-62cm – 24 – 24 ½)