4 gallon, pontoon compressor, honda, powered oil free, direct drive, honda gc160 ohc premium residential gas engine, tough resin overhead cam, ohc, for durability & quietness, compact combustion chamber, ohc design & uniblock construction reduce fuel consumption, internal timing belt provides quiet operation, precision engineered & machined components result in smoother engine performance, easy access oil drain, oil fill & spark plug, low maintenance, oil free, direct drive operation, patented pump design with two piece cooling system, increases cooling efficiencies, lowers operating temperatures, extends the life of the pump, 155 psi max pressure for optimum tool performance, "pontoon" style tank design with two 2 gallon tanks for job site portability, equipped with regulator, gauges, quick connect & cushioned handle grips.