hi Kiffie..I did a search
http://www.brother-usa.com/Homesewin...2#.UQvNYfJChf8 and I believe it is either item #SA 552 or #SA 537. Go to the page, click enlarge the images, note the measurements & compare with yours. Looks to me like it was intended for an embroidery machine, perhaps. Remember Brother also makes the Babylock..so you might want to do a search there.