The L/13 (Paul Meybauer) is an authentic private purchase screwback model, the L/52 (C.F. Zimmermann) is, I strongly suspect, a reproduction, and this without even seeing the obverse. There are, by my current reckoning, eleven manufacturers of the screwback variety of the Iron Cross, 1939. All screwbacks were private purchase pieces. It is important to know where the maker marks are located in order to differentiate reproductions. They are as follows: L/12, C. E. Juncker, Berlin L/13, Paul Meybauer, Berlin L/16, Steinhauer & L?ck, L?denscheid L/18, B. H. Mayer's Hofkunstprageanstalt, Pforzheim L/52, C.F. Zimmermann, Pforzheim L/53, Hymmen & Company, L?denscheid L/54, Schauerte & Hohfeld, L?denscheid L/55, Wachtler & L?nge, Mittwaida L/56, Funcke & Bruninghaus L/57, Boerger & Co, Berlin L/58, Rudolf Souval, Wien L/59, Alouis Rettenmaier, Schwabisch-Gmund It is important to keep in mind only L/56 (Funcke & Bruninghaus) and L/58 (Rudolf Souval) marked the screw plate. The other manufacturers marked the cross.