Detects slow, smouldering fires commonly produced by electrical fires or sofas and is less likely to react to cooking smells if fitted in the hallway next to the kitchen. Contains a sealed-in, tamper-proof 10-year lithium battery. Features built-in RadioLINK+ wireless interconnection technology which uses radio frequency signals to link alarms together for added functionality. All RadioLINK+ alarms and devices should be house-coded together upon install. Alarm is not powered until it is twisted on the mounting base, thus avoiding battery power consumption during storage and prior to installation. Interlinked via Wireless 10-Year Sealed Tamperproof Lithium Integrated Battery 85dBA Alarm at 3m Test/Hush Button Easy to Fit RadioLINK+ Technology for Interconnection Interlinked via Wireless 10-Year Sealed Tamperproof Lithium Integrated Battery 85dBA Alarm at 3m Test/Hush Button Easy to Fit RadioLINK+ Technology for Interconnection