1 x MG740PLUS Electric Bicycle. 48V 20AH 18650 Lithium battery. with anti-skid and anti-vibration function,and the span is longer.Biggerfaster, less effort. Optional imported Shimano 7-level transmission system,customized aluminum alloy crank 46T large chainring,front 1 rear 7-level classic combination,SIS po- sitioning,durable 7-speed greatly enhances riding fun.