The question mark is because I don't know if it is or not

. Found it in a box of miscellaneous items that had been in storage for a while. The one on the left (with the extended PC board) has a switch in the casing hole - it's black so not easy to see. It also has DB25 connectors. The other module (with the white pot in the hole) has DB23 connectors. I'm assuming it's for some Amiga product, possibly having to do with disk drives because of the DB23s, and might be orphaned if it required any other hardware/software - once it's been identified I might be able to look around and see if I have the go-withs. Anyone recognize it?