Safe-T-Alert 30-441-P-BL Black Surface Mount Propane Gas Alarm Designed for the Rugged RV Environment. Ideal for Class A Motor homes, Class B Van Campers, Class C Mini-Motor Homes, Travel Trailers, Fifth Wheels, Truck & Folding Campers. Advanced Technology. Alarm Mute button silences alarm while RV is ventilated. Rapid recovery sensor resets when silenced or reactivates alarm if dangerous levels of Propane remain. Reliable. 12 Volt power means no missing or dead batteries to replace. Innovative. Circuitry system designed to conserve battery power. Long Life, Self Cleaning Sensor. Maintenance free built-in sensor. Loud 85 dB Alarm. Alerts you to the presence of hazardous propane vapors. Approved. Meets RVIA/NFPA requirements. Listed to UL 1484 RV.