BATTERY POWERED SMOKE ALARM WITH RE

5.4 Inch Diameter x 1.9 Inch Depth; With Test/ Silence Button; Replaceable 9 Volt Battery Powered; Ionization Smoke Sensing Technology; LED And Chirp Low Battery Indicator; RV Approved/ UL 217 Approved; USA/ Canada; With 9 Volt Alkaline Battery/ Mounting Bracket/ Wall Plug/ Mounting Screw