In the photo of the bobbins, the one on the left is one I found in the Amica case. It is a slightly larger diameter than the class 15 that is on the right. It is solid on one side and "holed" on the other. The bobbin case is shown in the instruction manual and seems to be different than most. it has an additional hook to thread. I tried the bobbin case from my grandmothers case (class 15) and it did not work. I have emails out to quite a few parts sites. fingers crossed that I can find one. This thing is so quiet. and has a bunch of stitches. The needle bar does not change position but has a sliding plate on the bed. It's very interesting.