The Centerforce ® I Clutch Series is designed as a high-quality entry-level performance clutch for those in need of a superior stock replacement. Using the patented Centerforce centrifugal weights (where applicable) and premium friction materials, the Centerforce Stage 1 clutch system is perfect for applications with stock engines or mild power increases from minor bolt-on modifications. The Centerforce ® II Clutch Series utilizes a full facing disc with premium friction materials and a pressure plate with patented centrifugal weights (where applicable). Furthermore, static clamp load is increased via our patented machining processes; this combination allows superb holding power and maximum clutch life, making this clutch ideal for selected street/strip, off-road and towing applications. Pressure plate and disc sold separately on some applications. The Centerforce DFX ® Clutch Series is the competition-proven clutch package for select import and domestic applications. This DFX series is engineered for competition standards of quality and craftsmanship. The DFX series is aimed at high-end applications that continually demand increased integrity and holding-capacity. DFX scores big, not only with holding-capacity and strength, but also provides some of the best drivability from a race-inspired single disc clutch. The DFX series features the patented Centerforce centrifugal weight system (where applicable) and retains an easy pedal effort, thanks to Centerforce's patented ball bearing actuated diaphragm, for smooth engagements without detriment to the vehicle's release components. The Centerforce DFX performance clutch system is SFI approved for competition with Nodular Iron pressure plate rings and reinforcements designed to help prevent drive strap breakage and safety. Note: Due to the materials used, the DFX clutch series is more aggressive with less dampening; this can cause some additional drive train noise and/or chatter.