I have 4 bobbin cases and 2 301's. 2 are original and 2 are reproductions.I got the reproduction cases with one of the 301's that I bought. The reproduction cases work fine in either one of my machines. They have Japan stamped in them followed by what looks like a tiny y with a circle around the Y. I also just recently bought a 10 pk of bobbins that were not original but they work fine. They have no markings on them but I bought those from a Singer Sewing Centre (yep they still do have some) so I felt pretty confident that they would be fine.