"Excellence in Performance", backed by the best one-year warranty in the industry! MaXX/Race Rigid 4 Pad Heavy to very heavy pedal effort, aggressive engagement, quickest shifts, increased gear rattle; Moderate friction life, extended by ACT's exclusive diaphragm design, rigid design may increase spline wear; Carefully engineered, precisely assembled, accurately balanced, uses select ceramic friction materials for high heat tolerance and maximum performance; Recommended for race use only; 100% clamp load tested and dynamically computer balanced for smooth high RPM reliability AI4-XXR4 kit features a MaXX pressure plate for the serious enthusiast. ACT MaXX pressure plates use exclusive diaphragm design to increase clamp load, reduce deflection and maximize clutch life. All diaphragms endure a four-stage, heat-treating process for unparalleled performance. ACT pressure plates have precision cover stampings to provide rigidity and consistency. ACT's 4-pad rigid race discs are made with high quality, ceramic friction materials. The chrome-moly hub is heat-treated for strength and durability. The lightweight, rigid design allows for quicker shifts and smooth, trouble-free service. With the 4-pad rigid race disc, engagement is harsher, but shifting is faster. The 4-pad rigid race disc is well-suited for the smaller disc sizes in smaller engines.