This is a genuine OEM replacement part that contains the necessary parts for replacing the cylinder head assembly in lawn and garden equipment with gasoline-powered engines. The cylinder head maintains the airflow to the cylinders. This airflow is responsible for fuel combustion. If the cylinder head is cracked or broken, fuel combustion is not efficient. When the airflow is blocked or lessened due to cracks and damage, engine performance suffers. This is a complete cylinder head assembly kit. It contains the cylinder head, valve kits, cylinder head gasket, muffler stud, muffler stud assembly, valve springs and spring retainers, valve cover gasket, exhaust valve adjuster, carburetor gasket, carburetor stud, and insulator. All parts should be replaced when doing a cylinder head assembly replacement to ensure all parts are in new condition.The cylinder head assembly is sourced directly from the manufacturer. It is sold as an individual kit containing all the parts. The cylinder head assembly is designed for use in leaf blowers, wood chippers, tillers, log splitters, and other small engines manufactured by Troy-Bilt, Cub Cadet, MTD, Yard-Machines, and other small engines.