Q:  What do P7 M13 style magazines look like?

A:  P7 M13 magazines hold 13 rounds of 9x19mm ammo.  They are an ingenious double-stack magazine design that is easy to load, and very reliable.  Here are the new style "post-ban"/LE magazines (these are unmarked):

Q:  Are there aftermarket P7 M13 magazines available?

A:  No, none to my knowledge.

Q:  Are there "pre-ban" and "post-ban"/LE P7 M13 magazines?

A:  Yes, there are two versions of the P7 M13 magazine.  The one without the notch is the earlier version. You will notice that when you drop the non-notched mag during a reload there is a good possibility that the follower will get stuck in the top. The newer mags have a tab on the follower that stops in the notch thus preventing the follower from traveling too far up.

Thanks to "flya727" and "glenn" from PCT for this contribution