Nameplate with eagle and abbreviation. Abbreviation O.K.H. (Oberkommando des Heeres) means the High Command of the Army of the Third Reich. The presence of its marking suggests that the device was used by the German army. In connection with the earlier description of Bergraph as a technical recorder, this may indicate its military application (e.g., recording data from instruments in vehicles, artillery, or tests).

Analysis of the abbreviation O.K.H. and historical context

Search results clearly confirm that the abbreviation O.K.H. stands for Oberkommando des Heeres, i.e., High Command of the Army of Nazi Germany. It was the highest command of the land army (Heer) from 1935 to 1945. A device with such a nameplate was most likely manufactured for military needs, according to the specification and order of the High Command.

⚙️ Device characteristics

• Manufacturer and marking: The device is signed by the company Heinz Berens from Hamburg (marking "Hamburg 5" is a district or borough). The abbreviation "D.R.P." most likely means "Deutsches Reichspatent", i.e., German Reich patent.

• Purpose: As equipment marked with the abbreviation O.K.H., it could have been used for communications, calculations, navigation, or control and measurement in land army units. The presence of clocks (likely indicators or chronometers) and lamps inside suggests an advanced for its time electrical/measurement purpose.

• Historical value: The item is a tangible relic of military technology from the period of World War II. Its collector's value is enhanced by the readable nameplate with the emblem (eagle) and the official abbreviation of the command.