The BRK Brands, Inc. model No SCO2 is a battery powered single station combination smoke and carbon monoxide alarm specifically designed for residential and institutional applications including sleeping rooms of hospitals, hotels, motels, dormitories and other multi-family dwellings as defined in standard NFPA 101 Model SCO2 complies with UL217, UL2034, CSFM, NFPA 72, NFPA 720, HUD, FHA and other agencies that model their codes after the above agencies. They meet building codes where battery powered smoke and carbon monoxide alarms are required either separately or in combination. The BRK cat. number SCO2B/SCO2LB features a dual ionization smoke sensing chamber and an electrochemical carbon monoxide sensor, 9V battery powered, an 85dB horn, an End of Life and a silence feature. The SCO2B features a 9V alkaline battery and the SCO2LB a 9V long life lithium battery. Intelligent Sensing Technology? is designed to reduce nuisance alarms. Latching Alarm Indicator? remembers which unit initiated an alarm. The unit that triggered the alarm will store in memory or latch? the information and begin to flash the LED indicator 2 seconds on, 2 seconds off. The Perfect Mount? system features a gasketless base and a mounting bracket that keeps the alarm secure over a wide rotation range to allow for true alignment. A single button test/silence button eliminates confusion. Battery installation and removal can occur while the unit is mounted to the ceiling or wall via the side load battery compartment. Other Contractor Preferred features include a dust cover to keep alarm clean during construction. Two locking features are provided to prevent battery theft and/or theft of the unit. Designed for wall or ceiling mounting. Includes mounting anchors and screws.