X-Sense Wireless Interlinked Smoke Alarm Detector with Sealed 10-Year Battery, Interconnected Fire Alarm Conforms to EN 14604 Standard, Link+, SD19-W, 1-Pack RF Interconnected Model 1-pack

Detection Anywhere: Features wireless interconnection so that if one alarm is triggered, they all go off, and they stay connected using radio frequency with a transmission range over 820 ft (250 m) in the open air
Ready to Use: The multi-pack interlinked smoke alarm have already been interconnected for instant use, and you can connect up to 24 Link+ wireless alarms at a time
Customizable Wireless Network: For a customized network, add new alarms to the existing network, or disconnect the devices and create multiple networks
Battery Powered Smoke Alarm: Built with a 10-year sensor and powered by a sealed 10-year lithium battery that doesn’t need to be replaced
Premium Quality Material: This interlinked smoke alarm is made from an upgraded premium material that is durable, corrosion-resistant, and flame-retardant