Generac G085657/085657/85657 Field Boost Diode. Used in many of the Evolution and Nexus Air Cooled wiring harnesses as the field boost diode for the 4 wire.
Note that this is just the diode which is normally not meant to be field replaced. It's crimped into the harness and then covered in shrink wrap and will need to be replaced by the same means or better.
Generac replacement parts will also usually fit the following Generac branded generators: Honeywell, Guardian, Siemens, Carrier, Watchdog, Centurion, Eaton & Bryant.
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