First Alert Heat Alarm, Hardwired

BRK, First Alert, Hardwired heat alarm with 9V battery backup. 120V AC/DC 135F w/Rate-of-Rise Heat Alarm. Understanding Rate of Rise - This allows the unit to sense a heat rise and alarm prior to reaching the fixed temperature. The alarm will sound when the microprocessor senses a temperature rise of a set number of degrees per minute. This enables a more rapid response to a potential fire. Thermistor heat sensor. Latching alarm indicator - remembers which unit initiated an alarm. Two silence features - can silence the low-battery chirp for up to eight hours or temporarily silence an unwanted nuisance alarm.