Kids helmet suitable for boys small children sizes 44 49 cm 46 51 cm 49 53 cm 52 58 cm us sizes xs s m main colours red black number of air vents 5 safety features fly net reflective print safety light rear chin padding with chin pad inner padding removable size adjustments height adjustable wheel adjustment system headring strap adjustable features chin buckle snap enhanced protection for back of head lower edge reinforcement constructions co m