The Hosco 500K Push/Pull Audio Taper Potentiometer packs two functions in one, the pot works as normal on its own but built in is an independent double pole double throw (DPDT) switch which can be wired to add/remove pickups, coil splitting and tapping, series/parallel switching and phase switching just by pulling up or pushing down on the guitars control knob. The 500K Ohms resistance gives a brighter tone and traditionally used for humbucking pickups and its logarithmic audio taper is normally used for volume pots so the human ear can hear the volume change more smoothly (though now commonly used for tone pots as well). These are metric spec potentiometers with an 8 mm threaded shaft and coarse 18 spline knob mounting, the metric size is commonly found on guitars made in Japan and East Asia (Epiphone, Squier, Ibanez, Schecter, PRS SE etc.). To use metric knobs that have a set screw simply line up the set screw with the split in the shaft and tighten the screw. Mounting hardware is included.