Generac 10000021555 4.5L Electronic Throttle Control Valve (ETC) 75MM. Used to control the engine speed on the 4.5L engines. May also go by 'Bosch Actuator' even though this particular version is not made by Generac.
Generac replacement parts will also usually fit the following Generac branded generators: Honeywell, Guardian, Siemens, Carrier, Watchdog, Centurion, Eaton & Bryant.
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