Germany, Luftwaffe. A Civilian Technician’s Officer’s Cap Insignia GTRexclude the centre of the cap

the centre of the cap band features an additional insignia consisting of a padded dark green wool backer bearing a central non-ferrous metal tricolour cockade

Accompanied by a four stripe Overseas Service (War) Chevrons (four blue wool chevrons sewn upon brownish-green wool

They had to have knowledge of all guns duties

and "Diseases of the Conjunctiva

Germany, Luftwaffe. A Civilian Technician’s Officer’s Cap Insignia GTRexclude the centre of the capA stamped aluminum alloy cap badge, featuring a second pattern Luftwaffe style eagle (facing right), clutching a swastika in one talon, superimposed and centred on a multi toothed cogged wheel, the reverse is plain and bears the mark GES GESCH and three prongs, measuring 65. 42 mm (w) x 49. 23 mm (h), very fine.