concrete pumpers; garbage crushing machines; garbage compacting machines; trash compactors; hydraulic lift tail gates; movable loading and unloading decks for cargo containers and trailers; compressors for machines; pumps, namely oil or water pumps for machines and as parts of machines, motors, and engines; transmission gear boxes not for land motor vehicles; and cylinders, namely hydraulic cylinders for machines, motors, and engines; air compressors for vehicles