The RBX Interchangeable Hub seats to the propeller hub cavity in order to eliminate hub chatter and vibration while preventing spinning within the propeller. It features a one-piece rubber construction with anodized aluminum splines - no plastics to deteriorate. Hubs offer 10° deflection to reduce banging when shifting gears or hitting a submerged object. All RBX hubs are reusable if the propeller is damaged. Designed for use with the following: Evinrude/Johnson/BRP 90-300 HP (1991 and Newer) with 15 tooth spline and 4-3/4" gearcase, OMC/Cobra/King Cobra Sterndrives Model 800/Cobra/King Cobra (1991-1994) with 15 tooth spline and 4-3/4" gearcase.