Figured this would be the right forum section to ask because the topic in Armor/AFV doesn't get much traffic.

So in a different topic it looks like these were introduced on the M4A2 but which other variants had them and did all of those have them?

Reason for asking is that I have seen at least one of the later Shermans that supposedly should have them but instead they were one-piece and have just the vent tube and small plate over it at the rear.

Becoming a Shermanholic I'd like to know which of my models the two-piece ones need to be incorporated on.

Willem. As this forum is dedicated solely to wheeled vehicles, I do suggest you post your question to the AFV/Armor Forum despite your doubts. I think you will have success. Cheers and good luck.