FIRST ALERT SC9120A CO and Smoke Combination Alarm 0 - 120 VAC/VDC

BRK® Combination carbon monoxide and smoke alarm eliminates the need for two electrical boxes and features a permanently installed CO sensor and a dual. Ionization smoke sensor. Intelligent Sensing Technology™ microprocessor controlled to reduce nuisance alarms. Ionization Technology. Interconnectable up to 18 units (smoke and combination units combined). Alarm latch indicator automatically identifies which unit initiated an alarm. Single button test/silence eliminates confusion. Automatically performs internal self-tests.