Universal Security Instruments CD-9795 120-Volt AC/DC Wired-In Combination Smoke and Carbon Monoxide Alarm,Universal Security Instruments,CD-9795" /> Interconnect up to 18 units, 12 smoke alarms maximum; when one alarm goes off all units sound their alarm Silence feature - convenient silence button with automatic reset allows you to temporarily override an alarm - ideal for cooking smoke and fireplaces and eliminating nuisance alarms Audible low battery indicator; alarm and power test buttons. Includes a 9-Volt super heavy duty battery to power the alarm in the event of an AC power failure The alarm sounds with its loud 85 decibel horn and the red LED indicator flashes. A green LED light indicates AC power The quick-draw pull-out drawer makes battery replacement easy