This PREDATOR® 4200 Max. Starting Watt Dual-Fuel SUPER QUIET™ Inverter Generator with CO SECURE® has the capability to run on either gasoline or propane. Powered by a large PREDATOR® 187cc gas engine, this generator has a TT-30 RV outlet and an extra-large fuel tank that delivers over 8 hours of runtime*, making it an unbeatable value. The 4200 starting watts and 3200 running watts make this an ideal RV generator with enough power to run most air conditioning units. Automatic fuel switchover seamlessly transitions from propane to gasoline when the tank is depleted, with no need to shut down, providing over 20 hours of continuous operation.