9510, Replacement Potentiometer Kit for NEMA-4X Controls (PC, PW, RC, AC). The Potentiometer Kit consists of a 5K ohm linear potentiometer with mounting hardware and front panel insulation for use with NEMA 4X controls. The conductive plastic type is rated 1/3 watt and is fitted with a nylon shaft and isolated brass mounting bushing – black knob included.