I have DWM s/n 4136 no letter suffix. No “chamber date” on this pistol. This pistol has two inspection stamps and one proof mark on the left side of the frame. No dovetail milled on the rear of the frame. No “unit markings” on this pistol. All matching including one original matching magazine. A plus is the period holster with no year made by F.W. Kinkel of Mainz. It does have the hold open added by Erfurt.