You didn't say what frame you have, but I am pretty sure that the SureStitch Stitch Regulator is machine specific. I'm not sure And depending on which frame you have, you may need an adapter for it to work. The first one I got had an issue and I had to have it replaced by the Grace Company under warranty. If you have the number for them, call and talk to them. I found them to be helpful when I did.
Good luck!