I have 2 third series Diana 58 air rifles and have been doing a bit of research. It is said that the serial number is inside the tap. Below are pics of my tap numbers. The highest number tap number I see in the Gallery is in the 200’s. It is just hard for me to believe that they made this low a number of rifles. Isn’t more likely that these are some kind of batch numbers? The only written article I have on these rifles was written by Larry Hannusch. He says these are serial numbers but he then says that he thinks the rarer Second Series numbers manufactured may be in the thousands? Any thoughts. I guess if these were batch numbers we would have seen ducplicates?