A bunch of different companies built drives around that site, it was before the three and a half inch became standard.

I don't recall who made them, but I recall a three and a quarter floppy. Or maybe my memory's wrong?

And speaking of Matsushita setting up a dedicated production line for the 3-inch floppy drives, they will have done the same for the dedicated 2-inch floppy drives production line 5 years later:

https://youtu.be/YhKWMHN4m0U?t=67