Dual fuel inverter generator features CO Shield, the Carbon Monoxide auto shutoff system. Just add oil (included 10W-30), and operate your Dual-Fuel generator right out of the box on gasoline or propane, and easily switch fuels with the EZ Start dial. Designed with a low oil shut-off sensor. CO Shield technology monitors the accumulation of carbon monoxide (CO), a poisonous gas produced by engine exhaust when the generator is running. If CO Shield detects unsafe elevated levels of CO gas, it automatically shuts off the engine. CO Shield is not a substitute for an indoor carbon monoxide alarm or for safe operation. DO NOT allow engine exhaust fumes to enter a confined area through windows, doors, vents or other openings. Generators must ALWAYS be used outdoors, far away from occupied buildings with engine exhaust pointed away from people and buildings. Meets the requirements of ANSI/PGMA G300-2018.