Brand Name: BRK *Power Type: Hard-Wired w/Battery Back-up *Sensor Type: Ionization *Product Type: Smoke Detector *Number in Package: 6 pk *Packaging Type: Boxed *Test and or Reset Button: Yes *Battery Size: 9-volt *Warranty: 10 year *Width: 5.6 in. *Height: 1.9 in. *Length: 5.6 in. *Sound Level: 85dB at 10 ft. *Discovery -  Super,