This magazine was produced by ENM as indicated by the elongated weld spots. The magazine is stamped on the left side with P38 over U. Two stamps can be found on the spine: E/WaA706 above jvd. jvd is the secret manufacturer code assigned to ENM. E/WaA706 is the ENM inspection stamp.
In this case the magazine has a double stamped U and this is probably a factory error.
A very late mag which was issued with the 2nd alphabetic (serial number prefix a or b) Spreewerk production and with the 0-series Spreewerk pistols.