Description Heavy Duty Diode Board / Rectifier for Bosch 3-phase Charging Systems. Premium Quality Aftermarket diode board replaces Bosch Original Equipment diode board on ALL BMW Airheads models with a Bosch 3-phase Charging System 1969-1995. Includes robust Heavy Duty 12 gauge Wiring Harness. The new diode board design provides the latest in reliability and endurance under increased current demand and high heat conditions. Model:R45, R50, R60, R65, R75, R80, R90, R100  1969 – 1995 Manufacturer #: 12311244062