The Kidde 5COLSB Carbon Monoxide Alarm continuously monitors for the presence of deadly carbon monoxide (CO) in the home, providing a constant protection against the effects of this deadly gas. The 5CO features two LEDs - The red LED illuminates when the alarm has detected CO in the atmosphere and the green LED confirms that DC power is present. The alarm can either be installed on a wall or just placed on a tabletop or shelf for added convenience. It is also ideal for use when on holiday and in rented accommodation. The Lifesaver 5CO features a 7-year sensor life with an end of life warning to replace the unit after seven years protection.Additional Information:• Safety Type: Carbon Monoxide• Power Source: Sealed Battery