Except for the matte finish, it looks just like a Mark IV (same sight as the Mark IV and Mark VI, with the little set screw, but there aren't any leaves with it. I didn't know they had those on the Combat Master). I understand the sight came installed by the factory, and it is identical to one on a Mark IV. The box is just a white box, which I think Detonics was using for a time when it didn't have the oversleeve artwork, and the serial number and "matte blue" are written on the side. It might be a special order Mark IV (matte blue) or Mark I (adjustable sight). I noticed that on this website a transitional model "MC 1" that has a Matte blue frame and slide is mentioned, and the serial number is consistent with the change to the Caspian frame, at least from what I read on this site.