Military rang insignia of the German Democratic Republic until 1990, here:
Shoulder board capital letter F to Fenrich candidate (1st or 2nd year on a military technical school (comparable to OR-5 or OR-6, NATO)
Colour: black (field uniform), to –
National People´s Army, Land forces, Air Force/Air Defence, GDR Border Troops
GDR Civil defence
Ministry of State Security of the GDR.
NVA, Schulterstück