BRK CO511B (model CO511) is a single station CO alarm specifically designed for residential and institutional applications including sleeping rooms of hospitals, hotels, motels, dormitories, and other multifamily dwellings as defined in standard NFPA 101. BRK CO511B has been fully tested and complies with, UL2034, CSFM, NFPA 720 and NFPA 101 and other agencies that model their codes after the above agencies. It meets building codes where battery operated CO alarms are required along with wireless interconnect, voice with location and silence features and with model building codes published by the ICC. BRK CO511B is a state of the art wireless talking CO alarm designed to provide early warning of carbon monoxide. It features an electrochemical carbon monoxide sensor, an 85dB horn, a supervised 3V (2 AA batteries) power supply, a full function test switch and a silence feature. This combination alarm interconnects via wireless communication on a reliable and secure radio frequency communication of 915 MHz frequency with 65,000 security codes and 3 channel frequency hopping. You have a choice of 11 pre-programmed locations where a voice will announce the location and danger detected. When interconnected with other BRK Wireless Interconnect alarms it will also announce the danger and location detected of that alarm too. It operates on a Mesh Network; a two-way communication format that sends, receives and re-sends the alarm signals providing a more reliable network. It also features tamper resistant locking pins that lock alarm to the mounting bracket and battery drawer to prevent removal of battery or alarm. Perfect for apartment, dormitory or hotel applications. Designed for wall or ceiling mounting. Includes mounting anchors and screws.