My mistake, it was actaully marked on the flat of the receiver and it didn't look like that at all. It was in a straight line and was stamped 3 inch. or 3 in. That was all. I believe the barrel flats were also stamped the same but definitely not like your picture. MarketHunter saw this gun when I bought it but that has been years ago and I'm sure he has probaly altered his state of consciousness a time or two since then and maybe can't remember either.