Very rare Screwback 1939 Iron Cross First Class in LDO case by Boerger & Co marked L/57

An excellent condition screwback 1939 EKI manufactured with a silver-plated neusilber frame and a matt black finished magnetic iron core.
The core exhibits minor wear but is generally very good.
Frame crisp with a light age patina.
The screw fitting in perfect working order with the anti rotation spike still in place.
The backplate is stamped L/57, this being the LDO code for Boerger & Co of Berlin.
L/57 marked EKIs are classed as very rare by the collecting community, even more so the screwback variety.
The early quality black LDO case is in overall excellent condition. Manufactured from light wood and compressed cardboard. The base is of black velvet which is recessed for the screw plate.  The interior lid stamped with the LDO logo in gold foil.
Overall a very nice and extremely rare cased Boerger marked screwback Cross.