The Bell Ambient helmet is sleek, stylish, and a great helmet for a commuter or casual rider. It uses fusion-construction with 14 cooling vents for a lightweight, durable helmet. The PinchGuard ensures pinch-free buckling. The Mini Dial in the back allows for easy adjustment for a comfortable fit. The camlocks create an easy strap adjustment and it has a fashionable built-in brim. CPSC 1203 Bike safety certified. Fits head sizes 21.3-24.0" (54-61cm).