Bought a 220 in 45 ACP in 07. Never shot it and dug it out of the safe today. Noticed it is serial numbered on both sides of the frame and the W in West Germany is Xed out. No chin date. Internal extractor. Can someone please explain? Thanks in advance.

Here is another one, a CPO P220 from Osage with serial on both sides of the frame.
https://sigforum.com/eve/forums...0601935/m/4540024344

Is your gun's serial # right around 1995? If not, then it most likely is a parts gun that SIG put together, which is not at all uncommon with CPO guns.