ESR641 is a modern high quality regulator/rectifier that is a plug in replacement for the stock Honda regulator. We incorporated the latest generation of our Power Circuit and built it inside our efficient heat sink unit. ESR641 offers superior performance compared to the OEM unit. Voltage regulation is stable and the advanced heat sink ensures that our ESR641 runs much cooler than the stock regulator/rectifier. ElectroSport offers ESR641 with a full one year warranty.