Firex is the best brand for the carbon monoxide detector. It is the world’s leading manufacturer of fire & carbon monoxide detector products. Besides, the products of it prevent injuries and damages by notifying the people on time. There are also some models which contain a photoelectric sensor. It protects both fire & carbon monoxide sensors in one unit. However, it has a low-battery warning for portable CO readers. The red LED light will continue to flash every minute for the first hour. After that, the flash will be accompanied by the chirps’ sound. Above all, this alarm is easy to install & access. However, you can check out the other notable brands’ products. And they are Z Wave, Fire Angel, Safe T Alert, First Alert, and much more.