kids bikes 1, with good quality 2, classic design and advanced technology 3, competitive price kids bike size 12" to 20" . With best ... tyre of MTB type, E/V or A/V,12"x2.125 16"x2.125 20"x2.125 / EVA ... , thickness 1.2mm,argon-arc welding. 7.Chainwheel&Crank: 12"--24T*89, 16"--28T*102, 20"--32T*127, ED/ ... ; in one 40HQ ( CKD 4 SETS/SKD 85% ): 12"----2400/1150 SETS 16"----1900/800 SETS 20"----1500/580 ...