1/2" (12.5 mm) Panel Control w/Push-Pull Switch - 54 Series The Model 54 " panel control with push-pull switch is an extension of the Model 51/53 Series with an added double-pole, double-throw (DPDT) push-pull switch module. Model 54 Series potentiometer is an industrial grade product that allows the user the flexibility of a panel control plus push-pull switch function in one compact component. Model 54 is designed for use in various industrial, medical and aerospace/avionics applications.