BRK Electronics First Alert CO250B 9V DC Battery Operated Tamper Resistant Electrochemical Carbon Monoxide (CO) Alarm

9V Battery Electrochemical Carbon Monoxide Alarm with Silence. Electrochemical CO Sensor Silence Feature End of Life Signal provides audible notification alarms needs to be replaced Tamper Resistant Locking Pin 9V Battery Included 10-Years Limited Warranty Model # CO250B Weight 5.1 oz Dimension 4.25" dia x 1.6"H Operating Voltage 9V Battery Powered Temperature Range 40°F (4°C) to 100°F (38°C) Humidity Range 10% to 95% relative humidity (RH) Audio Alarm 85dB at 10 feet Test/Silence Electronically simulates carbon monoxide condition, causing the unit to alarm and silences unit. Alarm Reset Automatic when carbon monoxide clears CO Sensor Electrochemical Indicator Lights/Sounds DC Power: Intermittent red Light Listing Listed to UL 2034 Standard