Generac 6439 Guardian Series, 11kW Air Cooled Standby Generator, Natural Gas/Liquid Propane Powered, Steel Enclosed (Discontinued by Manufacturer) Unit runs on natural gas or liquid propane and features hands-free operation with no fueling, no manual start and no extension cords Clean, smooth True Power Technology provides safe operation of sensitive electronics Will require an automatic transfer switch 11,000 rated watts and this model is UL, CUL and EPA compliant for safety Comes with a 2-year limited warranty and is CARB Compliant