Mountain bike helmet suitable for men sizes 51 55 cm 55 59 cm 59 63 cm us sizes s m l main colour grey surface matt number of air vents 21 application all mountain chin padding chin pad not inlcuded inner padding breathable removable washable visor with visor adjustable 15 size adjustments wheel adjustment system headring strap adjustable construction in mold outer material polycarbonate weight 300 g inner material polystyrene eps he