Girls bike boys bike series puky z wheel size 12 inch frame material steel gear system without gears number of gears 1 rear derailleur singlespeed braking systems rim brakes coaster brake features padded handlebar bell chain guard bike frame size inch 9 inch rims aluminium frame geometry wave main colour red secondary colour blue theme stars recommended age suitable for ages 3 5 years inside leg measurement 40 cm frame alloy hi ten stee