The Kidde P3010H-CA is a 10-year, sealed battery, smoke alarm with photoelectric sensing technology and Hush feature. The 85dB alarm tone is accompanied by a voice warning feature. The alarm will automatically activate when it is attached to the mounting bracket; there are no pulltabs, no switches, everything is automatic. At the end of alarm life, the unit will chirp, indicating the alarm is in need of replacement. The P3010H-CA contains a 10-year tamper proof battery that eliminates the need for battery replacement, and ends worry of unauthorized battery removal.