Keep your head safe without breaking the bank with the Bell Piston bike helmet. This helmet may give off a casual vibe, but it is all business when called upon for duty. Fusion In Mold construction bonds the helmets outer microshell to its EPS foam layer to provide a sturdier, more solid helmet. ErgoDial fit system allows for one handed fit adjustments: simply press the button and slide the dial to get firm, snug, and comfy stability. Removable snap in visor offers a simple yet effective solution to harsh light situations. Cam lock strap levers make strap adjustments super easy: just open the cam, find a comfortable position, and close the lever again. 15 extra large vents help keep you cooler and more comfortable. Universal sizing fits head circumferences from 21.25 24 in. 54 61 cm.