Sierras 18-5303 Contact Set is designed for use with Ford and GM 4 Cylinder, 6 Cylinder, and 8 Cylinder engines with a Prestolite Conventional Ignition. Includes one contact set per package. It is interchangeable with select Mallory, GLM, CDI, Indmar, Crusader, Chrysler Inboard, Mercruiser Stern Drive, OMC Stern Drive, Pleasurecraft, and Volvo Penta part numbers. Each Sierra product meets or exceeds the original equipment part it replaces. Fit specific, check part numbers to ensure proper fit.