An optional alarm module is available to deter malicious manual pull station false alarms in applications such as schools, hospitals, transit facilities and other areas of mass congregation. When this option is provided, the integral alarm module will emit a piercing (104 dB ±3 dB at 1 meter) siren tone upon opening the cover to access the station. In addition to deterring malicious pranksters, the siren will provide an audible indication that the SENTRY Station Cover has been activated. The Alarm Module Kit consists of an alarm module, 9V battery, a silencer key, and two 6-32 x 3/8” Phillips pan head screws.