ESR318 is a high quality regulator/rectifier that replaces the OEM Honda regulator/rectifier on the TRX420 ATV models. Our ESR318 includes the latest generation power electronics and a highly efficient internal heat sink design which allows for cool running and excellent power characteristics. This regulator/rectifier is superior to the OEM unit. ESR318 output voltage is very stable which provides for a perfect charge rate for the battery, and it runs extremely cool due to the advanced circuit design. ElectroSport's ESR318 is supplied with a full one year warranty.