The GENMAX GM4000XiD-NFT DIY Open Frame Dual Fuel Inverter Generator, 4000W 120V ultra-quiet 145cc engine, with CO Alert. Parallel and Series Capability to turn 120V into 240V. Optional extended functions -extended electric start function, extended wheel armrest function, extended fuel tank function, extended gas cylinder installation function, extended toolbox function, etc. and the fuel circuit is quickly connected by a plug, which is safe and reliable.