First Alert Plug in Carbon Monoxide Alarm

Keep your family safe from carbon monoxide in multiple rooms with this convenient plug in carbon monoxide alarm 3 pack; The alarms work with any standard outlet and also have a battery backup for continuous monitoring of CO levels, even if there's a power failure, Features an advanced electrochemical carbon monoxide sensor that accurately detects carbon monoxide levels, no matter where the detector is placed in the room, Simple to use, with a single test/silence button; A loud 85 decibel alarm sounds when Carbon Monoxide levels reach dangerous levels, To ensure complete protection make sure to place 1 on each level of your home and in each bedroom, 7 year limited; Equipped with end of life signal chirp, so you know when it's time to replace the unit for safety, All First Alert CO alarms are rigorously tested to meet UL standards.