Operate your 4000-watt portable generator right out of the box on either gasoline or propane, plus features CO Shield carbon monoxide auto shutoff system, With an ultra-quiet 64 dBA from 23 feet, enjoy 4000 starting watts, 3000 running watts and up to 10 hours run time on gasoline, and 2700 running watts and up to 25 hours on propane, The optional, sold-separately parallel kit enables this inverter to connect with another Parallel Ready Champion Inverter or Power Station for more power and longer run time, Includes a 120V 25A TT-30R outlet, a 120V 20 A household duplex outlet (5-20R) with clean electricity (less than 3% THD), plus a 12V automotive-style outlet, and Parallel outlets, Includes 3-year limited warranty with FREE lifetime technical support from dedicated experts