Kidde 0976 - 2 Front Load Battery-Operated Ionization Sensor Smoke Alarm, 2-Pack Front load battery door provides easy access which reduces the installation time and battery replacement time Battery operated 9V battery included Hush feature temporarily silences nuisance alarms Unit can be locked to the mounting bracket to prevent the alarm from being removed from the ceiling or wall Kiddes smoke alarms meet the requirements of Underwriters Laboratories (UL), an independent facility that tests products for compliance with widely-accepted safety standards