The Kidde P3010H is a 10-year, sealed battery, smoke alarm with photoelectric sensing technology and Smart Hush feature. When smoke or fire is detected, the 85dB alarm tone is accompanied by illumination of bright LEDs to help provide a lighted escape path. The alarm will automatically activate when it is attached to the mounting bracket; there are no pull-tabs, no switches, everything is automatic. At the end of alarm life, the unit will chirp, indicating the alarm is in need of replacement. The customer can use a simple tool such as a screwdriver to deactivate the unit, stopping the chirp and making it safe for disposal. The P3010H contains a 10-year tamper proof battery that eliminates the need for battery replacement, and ends worry of unauthorized battery removal. The alarm provides continuous protection from smoke and fire, even during power outages. Industry experts (such as the NFPA), recommend that both ionization and photoelectric smoke alarms be installed to help ensure maximum detection of the various types of fires that can occur within the home. Ionization sensing alarms may detect invisible fire particles (associated with fast flaming fires) sooner than photoelectric alarms. Photoelectric sensing alarms may detect visible fire particles (associated with slow smoldering fires) sooner than ionization alarms. Learn more about worry-free alarms and view the video below. Worry-Free Alarms.