Generac Power System's commercial line of standby generators feature exclusive Quiet-Test for ultra-quiet operation during the unit's weekly self-testing period. When normal utility power is present, Quiet-Test allows the generator to run at reduced speeds, thereby lowering sound pressure by as much as 12dB. This is especially important in areas where residences or other businesses are close by. Clean, natural gas fueled. No diesel fuel storage or exhaust emissions to worry about. Great for larger homes and businesses. HTS transfer switches sold separately. U.S.A. All sales final. All warranty work will be performed in the field, by the manufacturer. Rated Watts NG kW 150, Engine Generac 6.8L V-10, UL Listed Yes, Transfer Switch No, Start Type Automatic, Dimensions L x W x H in. 115 3/16 x 36 25/32 x 54 25/32, Fuel Type Natural gas, Volts 277/480, Engine Cooling Liquid, Mounting Pad No, Enclosure Yes/ Steel, Auto Shutdown Yes, Engine Speed RPM 3,600, Phase 3, Battery Required Yes, Noise Level dB 76, Battery Included No. Auto Shutdown Yes Low oil pressure, high temperature, over speed and/or overcrank Meets 2009 EPA standards All generator sales are final Standby generators require installation involving permanent outdoor placement, electrical wiring and fuel source connections. We recommend the use of a trained professional for final connections of gas and electric.