For All Rivera Pro Clutch EASY ON THE HAND! HARD ON THE COMPETITION! Easy on the hand, but with increased pack pressure at higher RPM, Rivera's "variable pressure" PRESSURE PLATE ASSEMBLY is the best of two worlds. Easy to pull at the clutch lever when shifting, with a dramatic increase in clutching power under the influence of high horsepower for instantaneous engagement. Up to 60% more pressure (clutch pack compression) enabling the use of a lighter diaphragm clutch spring for up to 50% easier clutch lever effort with no loss of performance. The TPP Variable Pressure Clutch is for use with all Pro Clutch models, and fits under most OEM outer primary covers with stock derby covers (except 2006 Dyna). World famous Rivera "Quality & Performance" since 1973. US Patent Pending No.10/558,301