Important: Must not be used in combination with lithium batteries.

From Electrosport in the USA They say it 'is a high quality regulator/rectifier unit that will replace the original separate regulator and rectifier that were part of the BOSCH field rotor alternators on BMW and Moto Guzzi models.

The ESR450 comes ready to be installed with a long wiring harness attached that connects directly to the alternator stator and to the brushes. The output wires are connected to the battery terminals making this setup highly efficient as we do not have to rely on the (oftentimes poor) original wiring and connectors.

After installing ESR450 in this BOSCH alternator system you will notice vastly improved stability of the battery voltage resulting in a healthy battery charge rate at all times.

ESR450 DOES NOT SUPPORT THE CHARGE WARNING LIGHT FUNCTION - The warning light will always be off.