The Case IH 717789R91 is a genuine OEM pinion designed for use in various Case IH agricultural tractors. This critical driveline component ensures reliable power transmission and is compatible with models including 766, 966, 1066, 1466, 1566, 1086, 1486, 1586, Hydro 100, and Hydro 186. Manufactured to original equipment specifications, it provides durability and precise fitment for optimal machine performance.