MSD has put a great deal of effort into researching and testing a variety of metallurgical compositions, heat treating and coatings to provide you with a durable, accurate and strong distributor gear. MSD engineers have built test fixtures and spent hundreds of hours testing and evaluating the metallurgy of our gears. The result is a special iron alloy gear that is treated to a low-friction coating process. To you this means long life, an easy break-in period and reliable performance!