Bmx helmet suitable for men sizes 46 52 cm 52 58 cm 58 63 cm us sizes xxss ml xlxxl main colours green black number of air vents 12 safety features reflective print chin padding with chin pad size adjustments wheel adjustment system pads features magnetic closure constructions in mold hardshell outer material polycarbonate weight 250 g inner material polystyrene eps helmet technologies fidlock coolmax pads