when I bought my used Gammill, it included a Towa for the bobbin--sad to say, I haven't really figured out how to use it--you still have to know the numbers for the different types of thread and I don't have that--is there a chart? But I did watch the Jamie Wallen YouTube and he does an excellent job of explaining how to get good tension. One thing I have found out the hard way, is that when I use a Glide or similar thread (not with So Fine though) I need to put a "sock" on the thread cone on the machine, as this very fine, slick thread seems to come off the cone too fast and it messes up the top tension, slides out of the intermediate tensioner, etc.