CARBN MNXD DETCTR 9V 2PK *Brand Name: First Alert *Power Type: Plug-In w/Battery Back-up *Sensor Type: Electrochemical *Product Type: Carbon Monoxide Detector *Number in Package: 2 pk *Test and or Reset Button: Yes *Packaging Type: Carded *Battery Size: 9-volt *Batteries Included: Yes *Warranty: 7 year Limited Parts and Labor *Discovery ACC, SUP