WIDE APPLICATIONS: Suitable for most overhead valve engines, valve stems from 4.5 to 7.5 mm and 5/16″ to 3/8″. The new smaller size works for Toyota four cylinder and for Chrysler New World Engine applications. FEATURES: Makes valve component disassembly and reassembly quick and easy. Push or tap the tool with a hammer to remove valve keepers. The magnet in the tool body captures keepers for quick removal and valve disassembly. EASY TO USE: To install keepers, load in the retainer on the valve stem, then push or tap the handle to install. Can be used on a car or bench. .