NOTE : OPERATES LINKED TO WIRED FIRE ALARM PANEL 230V mains-powered smoke alarm with 9V battery back-up. Features a high quality optical sensor for optimal smoke detection, with fewer false alarms. Can be interlinked with up to a total of 20 mains-powered fire safety devices, including smoke, heat and CO alarms (meaning that when one alarm sounds all interlinked alarms will also activate). Suitable for use in hallways, landings, living rooms, dining rooms and bedrooms. Supplied with fixings. Interlinked when Hardwired 220 - 240V AC/DC Mains-Powered with Battery Backup 9V Battery Supplied 85dB Alarm at 3m Test/Hush Button Interlinked when Hardwired (20 Alarms can be Interlinked in 150m) Fast Fix Base Supplied for Quick & Easy Wiring Silence Nuisance Alarms Low Battery Warning