Pinion bearingFits Mercruiser MR, Alpha I, Alpha Gen II Fits Mercury / Mariner V6 1982 to current, Also Fits Johnson / Evinrude V4 & V6 1978 - Current (4.750" diameter gearcase only) Also Fits OMC sterndrive 1978 - 1993 Stringer and Cobra 4.750" Diameter gearcase only