I have wound my own bobbins so that I can use a matching color thread, and I use the bobbins for my two Bernina home machines. They are exactly the right ones. My Berninas are a 1630 and 730E, which is the best way I can tell you the type of bobbin (don't know the exact Bernina number or whatever). I have a friend (NO business connection other than being a satisfied customer) who sells lots of machines and parts, mostly vintage machines. She said she has bobbins of this type, and you can contact her via stitchesintime@xxxxxxxxxxxxx I am gonna order some soon, there never seems to be enough bobbins unless you like either layering thread on top of other thread (don't go there) or taking thread off. These bobbins have a "gripper" center so it is a bit easier to wind the thread than it is on the old fashioned bobbins with just a smooth metal finish. I just email her to ask if she has the "anti-backlash" spring people have discussed using, although these bobbins run fine as is (with embroidery thread wound on them, usually). Carol Brussel Brussel Embroidery Denver