1Fitment: Replacement for Aprilia RS660 2021; Replacement for Aprilia Rs 1100 RSV4 Tuono 2021 2022, reference part number is SH870AA. 2Function: The rectifier uses a semiconductor diode to conduct current to rectify and control the power supply, provide a stable voltage for the battery. 3Fuel Saving: Voltage regulator can improve ignition efficiency, make fuel combustion more adequate and reduce the use of vehicle fuel. 4Direct Replacement: Motorcycle voltage rectifier can replace the old regulator to improve light dimness, making the lights brighter than before. 5Characteristic: The rectifier adopts surface mount technology with strong anti vibration and anti interference ability and has been strictly checked to meet the quality standards.