Turning Point's Hub Kit Systems are engineered to withstand typical wear and tear over time without risk of spinning or failure under normal operational use. Hub kits feature a unique patented one-piece hub with glass-filled nylon over brass splines to eliminate failures commonly seen in multi-part "sleeve and spline" designs and pressed-in rubber hub systems. Glass-reinforced high-tech polymer construction increases flexibility, eliminating potential stress fractures. High flow-through barrel exhaust system maximizes exhaust flow to increase horsepower and top end speed. Clear step-by-step instructions make installation easy. Propeller Housings are sold separately. MasterGuard 25 Hub Kit Only - 10 tooth spline. MasterGuard 25 Applications: Parsun/Yamaha• 20 - 30 HP engines with 3" gearcase One-piece hub design Glass-reinforced polymer for flexibility Maximizes exhaust flow for more horsepower | MasterGuard 25 Propeller Exchangeable Hub Kit