Predator 68525 Natural Gas Propane Conversion Kit uses an adapter that makes it possible to operate an engine on three different fuels Propane, Natural Gas, and Gasoline. Adapters will mix the Propane or Natural Gas into the air stream above the gasoline carburetor. The gasoline carburetor remains basically untouched. So this kit is not a conversion, it is an adaptation. Generator Frame does not need to modified! NOTE: The C-039-122 fuel regulator that comes in this kit ONLY accepts vapor fuel pressure that is 6 - 8 ounces per square inch, which is the equivalence of 11 inches of water column. If you need to run off a barbeque tank(portable propane tank), additional parts are sold separately to run on a portable propane tank (Part Numbers:SEK-05A or SEK-05-12A). Please check out our Conversion Kit Accessories. Please note that our adapter may cause air disruption when attached to carburetorair cleaner assembly. You may need to remove our adapter if you want to run on gasoline.