Boxes are damaged , items complete and good condition. The Kidde Hardwired Smoke Detector with AA Battery Backup is a reliable and essential home security device. This 4-pack of white smoke detectors from the reputable brand Kidde features a hardwired power source with a battery backup for continued protection even during power outages. Each detector has a diameter of 5 inches and comes with two batteries included. With the interconnectable feature, these smoke detectors provide a comprehensive solution for ensuring safety in your home.