[Dr Teeth]

I have a general question here what are the number on the back of the casting? B19/ B21. What do those numbers mean and is it rare or unusual for the same car to have two diferent numbers like that. I have two mystery corevette grand sports with two different numbers on them. They are the same casting. Just wanted to know this info thanks in advance

 

[McRooster]

They are manufacturing shift and date codes.

 

[chriszamac]

there a code that matel uses now
i belive a date code as to what date the item was made
yes it is common to have the same car with 2 diff codes
also crition varis can be found only on critien # base i belive the clear window carmaros have a diff # than the tinted windows

 

[CTWLSMIKE]

I've heard that the number corresponds to the week of the year but I don't know if that is confirmed.