rear Impact absorbers.

Hey guys hope everyone is doing well,i know some of you guys here are really good at knowing all the nuances on these cars and why in certain years they used certain hardware or a different sensor etc

Today i was curious about the rear bumper impact absorbers and why are there 2 kinds, as well as i know Ford (or i think i do) they just didn't put some on a car Wednesday and the other kind on Friday, there has to be a reason or they are year specific or ones are for the 4 bangers and the others for V8, let me know your thoughts.

I stole these pictures from a seller on Ebay,i hope he doesn't mind,if all it might send some business his way,,thank you much for your input in solving this mystery for me.

I just wanted to edit my comment and add, it seems the ones in the first picture would be much stronger than the second ones, just my observation, maybe a recall deal?

Yeah, I think they used both, i thought for a minute one might hace been for the front but the front ones are different where they attach to the bumper.