I have the Brother 1500 with the 3 hole bar. I only use the first hole as a guide, not for tension. A Brother tech told me he had no idea why that bar was there, it caused too many problems. It is suppose to be to add stability to specialty thread and he had no idea what type of thread that would be. It will, if all three holes are used, put a lot of tension on the thread cutter causing it to unthread the needle.