The NCM Alarm Unit will hold one Network Control Modem (NCM) and is used at the PSAP site. It will give an audible and visual signal when the alternate answer circuit monitored fails. The NCM Alarm Unit has switch for PSAP personnel to activate the NCM card to send a signal to the tandem switch to re-route the 9-1-1 calls to an alternate PSAP. The NCM Alarm Unit can also be wall mounted with a bracket supplied.