Little Help

[splitfish]

I recently went to a gun show and brought along my Luger, I learned a lot about it but there are some characters stamped on the grip that have always interested me. They gave me a brief description on what they meant but referred me to this site to learn more. I'm hoping someone out there can tell me exactly what they mean. Any help would be much appreciated, this Luger has been in my family for 4 generations now, I'd love to learn where it came from and how my great grandfather ended up with it. I know these letters and numbers can't tell me all that but maybe they can point me in the right direction. Thanks again!