... rim or aluminum alloy rim 3.Size: 16", 18", 20", 24" 4.Color; Red, blue..... New model children bicycle, 16",18 ... ",20",24" unicycleModel No.: U-16A (16", Aluminum rim or stell rim ... , 1734pcs/40' HQ new model children bicycle 16' 18' 20' 24' unicycle bicycle