[saxman]

I would not speculate as to value, perhaps someone more knowledgable will. Most police Lugers were converted to have a sear safety, which has a rather obvious lever on the left side of the frame which works through a slot in the top of the sideplate. They also have a magazine safety which requires a short vertical cut on the left side of the frame. Yours is obviously a police Luger with that unit designation, but it doesn't necessarily have to have the safeties. I'm sure you can find some pics on this site of police Lugers.