What is this part called...

[siegersallee]

Hi all,

I have looked all over the internet to try to find out the name of a particular part of a Luger...all to naught.

The part in question:

On left-hand-side of the of the pistol is the magazine release.

The magazine release covers a pin that extends through the frame and terminates on the right-hand-side of the pistol.

On Erfurts, on the right-hand-side, this pin has a proof marking and is "strawed".

I have uploaded a pic to help understand what part I am asking about.

Does this pin have a name?

thanks,
Richard