These jumbo bobbins will fit the following machines:

9 Series - B 990

7 Series - B 700 710 720 735 740 750 QE 765 770 770 Plus 780 790 790 Plus 790 Pro 790 Ultra

5 Series - B 500 535 540 570QE (2nd Generation) 580 Liberty 590

4 Series - B 435 475 QE 480 495