I use Cotton, So fine, King Tut, am am going to try the bottom line in my regular sewing machines. With my Long Arm it was recommended to use the So Fine(less lint), also that the King Tut and Bottom line would work fine with it to just to thread differently and thread horizontal rather than vertical. I haven't used it yet but there is a Glow in the dark that I can't wait to try. Love Superior Threads Company!