Visonic Wireless Carbon Monoxide CO2 Detector MCT-442 Fully wireless and supervised detector transmits alarm and functionality alerts to the PowerMax control panel, which notifies the user and/or the central station Gives early warning of carbon monoxide (CO) poisoning danger, providing visual and audial alarm indications when CO is detected Loud built-in alarm buzzer (95db) and a large flashing LED alarm Battery operated, ensuring continuous protection; low battery and sensor end of life indications Easy wall or ceiling installation (with bracket), with no need for cabling work; simple battery replacement