The Ei Electronics EI450 RadioLink Alarm Controller is a white smoke alarm unit with a diameter of 15 cm, depth of 4.5 cm, and width of 10.5 cm. It is powered by a battery with a 10-year manufacturer warranty. This alarm controller is compatible with Google Home for smart home integration and features a battery backup for continuous protection. With an operating sound rating of 90 dB, this alarm controller from Ei Electronics is a reliable and efficient choice for home security. Reduced to clear exp2030 sold as seen