I take it all back! I see what you mean now Florent.
I had thought that you were referring to an inner metallic chapter ring of the type that you see on all early Polerouters. You do see these chapter rings on some of the 869115 dial variations e.g. 869115/02
On close inspection of the photo, I agree that the OP's watch seems to be missing a thin metallic outer bezel that surrounds the crystal. Here's a picture of another that shows that bezel.