The P4010ACS-CA is an AC/DC powered smoke alarm with 10 year battery backup that features interconnect capability and provides enhanced intelligibility for users. The voice warning feature accompanies the 85dB tone during an alarm event, and helps reduce confusion with verbal announcements such as “Replace Alarm” at end of alarm life, and “Hush mode activated” when a nuisance alarm is silenced. The three color LED ring helps users quickly determine standby, alarm, or error mode of the alarm. Kidde P4010 Series Alarms contain 10-year tamper proof batteries that eliminate the need for battery replacement, and ends worry over unauthorized removal. The unit's Ambient Light Sensing feature, which establishes a day/night cycle and prevents alarm chirping in dark conditions. Hardwire interconnect triggers each connected alarm to sound once smoke is detected. This can provide more time to react. Model P4010ACS-CA Power Source 120 V AC, 60Hz 53mA max per alarm with sealed 3V battery backup Sensor Photoelectric Audio Alarm 85dB at 10ft Temperature Range 4.4˚C (40˚F) to 37.8˚C (100˚F) Humidity Range up to 95% relative humidity, non-condensing Size 14.2cm in diameter x 4.9cm depth Weight 0.27 kg Wiring Quick connect plug with 15.2 cm (6”) pigtails Interconnects Up to 24 Kidde devices(of which 18 can be initiating) Warranty 10 year limited