This box was acquired on ebay. A web search and Electronic Technical Manuals Online search found nothing. Honeywell Sensing and Control
The title on the name plate says "alarm set, anti-intrusion restricted area". Maybe this box is part of what amounts to a fancy burglur alarm, or maybe it is some type of sensor in that system. It has 3 multi-pin connectors and provision for 2 each 9 volt batteries. The box appears to be hermetically sealed by soldering the case and the use of connectors that are glass sealed.Brooke's, Military Information, Home Page
One of the connectors has 3 pins, two of which are grounds making it a good candidate for the power plug.
From the Air Force Communications-Electronics Managers Handbook:
It is an exterior intrusion detector.
AN/GSS-26A Magnetic Anti-Intrusion Detector/Magnetic Intrusion Line Sensor - MAID/MILES: The AN/GSS-26A consists of one pickup assembly, one shorting plug assembly, and one motional pickup transducer (line sensor). The line sensor reacts electrically to ferromagnetic material in a vehicle,weapon, or item of apparel which may be driven, transported, carried, or worn by an intruder. The line sensor also reacts electronically to ground pressure changes and vibrations. The electrical output of the line sensor is the input to the pickup assembly. The pickup assembly electronically amplifies and analyzes the line sensor input signal. If the inputs have the required characteristics, they cause a switch in the pickup assembly to close. This switch closure completes a circuit causing the annunciator to indicate an alarm condition. The shorting plug assembly completes the power circuits between the battery assembly and the pickup assembly's electronic circuits.If you have info let me know.