The Generac MK3/MKIII Programmable Exerciser is a digital adjustable exercise timer that is commonly found in the Generac GTS Transfer Switches. This is a direct replacement part.
Also available is a retrofit adapter harness found here:
Generac 0C2347 MK3/MKIII Programmable Exerciser Retrofit Harness
Generac replacement parts will also usually fit the following Generac branded generators: Honeywell, Guardian, Siemens, Carrier, Watchdog, Centurion, & Bryant.
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