Eccentric Systems P500 double chain, single bass drum pedal, with QT CAM

Demo model, used, light scratches, no damage.  This is a very smooth, well-built pedal.  The Quick Torque cam gives it additional adjustability.   Read about the QT cam below from a sales brochure. 

Developed in the '80s, the Eccentric Drive Cam for for kick pedals became an industry standard and the Eccentric Systems Quick Torque Cam is the next evolution. The Quick Torque Cam replaces the return spring arm on most bass drum pedals. Using an Eccentric Cam on the return spring reduces the pressure required to push the pedal down, while multiplying the return force generated by the return spring. The yield is that the pedal returns the beater 30% faster with less spring tension which provides more impact.

Adding the Quick Torque Cam provides a much smoother operation and faster response while the process of converting pedals to use this cam takes just a few minutes and makes no permanent changes to the original pedal. The adjustable eccentric curve of the Quick Torque cam improves how the return spring energy is captured and released. By better controlling the spring, more input force is converted directly to impact while the cam concentrates the return force to snap the beater back with higher torque.

Quick Torque cams drastically improve performance on most any bass pedal from any of the major brands including Big Dog, Ludwig, Slingerland, Camco, Mapex, Sonor, ddrum,, Pacific, Tama, Gibraltar, Pearl, Taye, Gretsch, Premier and Yamaha.