This is a genuine OEM McCormick 404091R1 pinion, designed for reliable power transmission in agricultural machinery. Featuring 10 precision-machined teeth, this pinion is a critical component for the differential or final drive assembly. It ensures proper engagement and smooth operation, maintaining the performance and longevity of your equipment. Compatible with a wide range of International Harvester and McCormick tractor models, it replaces original part numbers such as 404091R1, 404091R2, and 404091R3.