FG-250RV Smoke Detector – 9V Battery Powered. BRK Model FG-250RV is a single-station smoke alarm specifically designed for RV, residential and institutional applications including sleeping rooms in hospitals, hotels, motels, dormitories, and other multifamily dwellings.Features: Dual Ionization sensing chamber – Generally more effective at detecting small particles produced by flaming fires, such as paper or kitchen grease. 85 dB alarm horn at 10 feet. 9V battery included. Full function test switch . Silence feature to silence unwanted nuisance alarms . Red LED light that indicates DC power or alarm . Tamper-resistant locking pin that locks alarm cover to prevent removal of the battery . Approved for RV use but can be used in apartment, dor­mitory or hotel applications. The compact, low-profile design complements any decor. Dimensions: Diameter: inch 4.25′′. Height: inch 1.6′′.