COMMFONE
ELECTRONIC FIRE ALARM AND VOICE COMMUNICATION SYSTEM FOR USE IN LARGE BUILDINGS, COMPRISING A CLOSED CIRCUIT TWO-WAY TELEPHONE SYSTEM WITH A MASTER STATION MODULE AND A POWER SUPPLY MODULE; AND OPTIONAL COMPONENTS COMPRISING JACKS, HANDSETS, ANNUNCIATION, ZONED COMMUNICATION, DOOR LOCKS, ARMORED CABLE, BATTERY STANDBY, AND TAMPER SWITCHES TO AUDIBLY AND/OR VISUALLY NOTIFY OF MISUSE
Expired · November 11, 1974 · 73036906 ·