Gottlieb Pinball Relay Coil R-20-4 A-9735: Relay coil commonly used as a pop bumper relay. 15 ohms. Reference:A-9735. Equivalent to part #:A-489, A-3891, A-7676, R-20-4, Wico 03-309800. Weight: 0.25 lb. Part Number: A-9735