Generac Guardian Series 5504 17,000 Watt Air Cooled Propane/Natural Gas Powered Home Automatic Standby Generator With Transfer Switch (Discontinued by Manufacturer) Convenient, hands-free operation with no fueling. No manual start. No extension cords. Runs on natural gas or liquid propane. Clean, smooth True Power Technology provides safe operation of sensitive electronics. Patented Quiet-Test low speed exercise mode Includes automatic transfer switch with 16 circuits protected (NEMA 1, indoor rated only) 17,000 Rated Watts. CARB Compliant.