Beebug Disc Buffer
Here's the item from the top. It looks like a podule, as it has a metal plate to fit to the rear one it, but it isn't long enough to reach the backplane and it doesn't have a podule connector. Instead, it has a 34-way ribbon cable to connect to the motherboard floppy drive socket, and it has its own socket on the back. It also needs a separate 5V power supply, provided by the two flying leads.