Originally Posted by ccthomas
I was so stupid I did not "see" that "Singer" bobbins were different heights. After spending a sewing doctor fee to learn that my "problem" was using the wrong height of a Singer bobbin, I would say YES, be careful. I felt so DUMB.
Brother bobbins are the same way. the size my ULT takes is SA 155 (3/8 inch). my DD's machine-a small, lightweight Brother takes a different size, SA156(1/2 inch).