The P4010ACS-WCA is an AC/DC powered smoke alarm with 10 year battery backup that features wireless 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 colour 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, prevents alarm chirping in dark conditions. Wireless or hardwire interconnect triggers each connected alarm in the network to sound once smoke is detected. This can provide more time to react. Kidde wireless units can be joined with the touch of one button.