Slim design Dual CO and LP Gas alarm. Alarm Mute button silences alarm while RV is ventilated. Rapid recovery sensor resets when silenced or reactivates alarm if dangerous levels of Propane or CO remain. 12 Volt power means no missing or dead batteries to replace. Cutout Dimensions: 3.5" W X 2.5" H. Includes optional trim ring to cover large cutouts. Meets RVIA/NFPA requirements. Listed to UL 1484 RV and CSA 6.19.