I have an Inter 10. I *think* the serial number is 6012750, though only the top parts of the 1 and 2 are visible, so I suppose it's possible they are a 4 and 3 respectively.

Actually, there are two numbers on the bottom part of the frame. The other one looks like this: [ ] 00315. And there other stray letters and numbers: an A and a 4 superimposed upside-down on the 00315 number, and a stray 5 off to the side. Can anyone tell me what those symbols mean?

I'm also hoping someone can tell me the year of manufacture...I'm thinking 1978 or 1979.