The H Mk III, Field telephone set was designed to provide secure wire communications on the front lines.
These sturdy field telephones have a painted steel outer box measuring 25cm X 11cm X 14.0 cm for both with a hand cranked magneto generator to “ring up” the other party. There are also instructions on the inner lid, and connectors for the wire with a heavy sound powered handset.
These were made by S.B. & Co., Ltd.
