"Excellence in Performance", backed by the best one-year warranty in the industry! Sport/Perf Street Rigid Light to moderate pedal effort, smooth engagement, increased gear rattle; Longer clutch life achieved through ACT's exclusive diaphragm design, rigid design may increase spline wear; Carefully engineered, precisely assembled, accurately balanced, with premium organic friction materials for heat tolerance and reduced fade; Recommended for street and race use; 100% clamp load tested and dynamically computer balanced for smooth high RPM reliability AI4-SPSD kit features a Sport pressure plate for a nice upgrade. ACT Sport 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 Performance street rigid-hub discs feature premium organic materials with high copper content for better heat transfer and steel-backed lining for greater burst strength and durability. The chrome-moly hub is heat-treated for strength and durability. Rivet design and materials are carefully selected for maximum strength. These discs are the minimum weight street disc for faster shifts. ACT's street rigid-hub discs provide race-proven performance with street manageability.