... classic design and advanced technology 3, competitive price kids bike size 12" to 20" .children bike1.Size:12 ... "-20"2.Bike frame:steel,stoving varnish ,thicker argon-arc welding/ ... CO2 welding,3.Bike from fork or rear fork:steel and painting, ... .11.Freewheel:12"-16T,16"-16T,20"-18T,single speed.heat treatment.finish:black or brow,or sliver. ...