"Excellence in Performance", backed by the best one-year warranty in the industry! 4 Pad Rigid Race Disc Aggressive engagement, quickest shifts, increased gear rattle; Premium ceramic friction materials provide moderate wear rates and high heat tolerance, rigid design may increase spline wear; Lightweight rigid design, chromoly hub is heat-treated for strength and durability; Recommended for race use only; High burst strength and holds 28% more torque than typical organic materials 4228015 is a 4-pad rigid race disc made with high quality, ceramic friction materials. The disc engagement is harsher, but shifting is faster. The race disc features top grade rivets to securely fasten the part together. The rivet design and materials are carefully selected for maximum strength. The 4-pad rigid race disc is well-suited for the smaller disc sizes in smaller engines.