This newly designed helmet from Bell combines style and functionality. Sleek and low profile, this helmet comes with the Spin Action Fit system and adjustable nylon straps for easy adjustment for the perfect fit. 21 aerodynamic cooling vents let you feel the breeze and stay cool and protected. Extended rear coverage provides additional protection. CPSC 1203 Bike safety certified. It fits heads sized 20.9 to 23.6 inches.