First Alert SCO2B Single Gas Detector, 10 ft, 85 dB, Alarm: Audible/Visual, Electrochemical Sensor, White

State of the art smoke and CO combination alarm designed to provide early warning of a fire or carbon monoxide danger. Has a dual chamber ionization smoke sensor and an electrochemical CO sensor. Loud 85 dB alarm, low battery warning. End of life alarm chirps when it is time to replace detector. Operates between 40 deg F (4 deg C) and 100 deg F (38 deg C) and relative humidity between 10 and 95%. Two latching features: alarm latch to easily identify initiating alarm after alarm condition has subsided and low battery latch: to visually identify which unit is in low battery condition. Intelligent Sensing Technology helps reduce the number of nuisance alarms. Includes dust cover, mounting anchors and screws. 9 V alkaline battery included. 7 years warranty.