74139568
Feb 15, 1991
electronic security and fire alarm systems; namely, encoded card readers for use as door access control systems, alarm sirens, smoke detectors, fire detectors, door and window opening detectors, motion detectors, automatic telephone transmitters, automatic radio transmitters, and microcomputer based central control units therefor
Electrical and Scientific Apparatusmanufacturing of electronic, security and control systems and transaction cards to the order and specification of others
Treatment of Materials