These were sold in folders of four cards each. The folders were coded 0600A and so on. I had to make up a code for the individual cards. You'll see... 0600A-1 0600A-2 0600A-3 0600A-4 0600B-1 0600B-2 0600B-3 0600B-4 0600C-1 0600C-2 0600C-3 0600C-4 0600D-1 0600D-2 0600D-3 0600D-4