Most likely a Compass holder.

Why not email the company that made it.
http://www.cplath-hamburg.de/die-manufaktur/cplath-geschichte.html

History.
1929 – Graf Zeppelin continues with C .Plath Dragonfly Sextant around the world Captain Witte man familiar with the world trip with the airship Graf Zeppelin, the most successful airship in the world and the only one that ever flew around the globe, on a Dragonfly sextant of C.Plath. 1939-1949 – Explosive growth, ban on production and Successful New Start The high demand for compasses and other navigational devices during the 2nd World War leads to a rapid expansion of the company – the number of employees increased from 1933 to 1942 from 34 to 650 people. After the war C.Plath is forced to reduce the production of precision equipment.