P/N 21027326 - The P4010LACS-W is an AC/DC powered smoke alarm with 10 year battery backup that features supervised wire-free 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.