The Model DSM fuel fill station monitor for diesel fire pump applications serves as a “Stop Fill” visual and audible annunciator. With its NEMA 4X enclosure and standard supplied anti-condensation heater and thermostat, the DSM is built to be installed outdoors near the diesel fuel fill pipe. The dead front enclosure makes it vandal-proof so the DSM does not need to be mounted high off the ground to avoid being vandalized.