Jumbo Bobbin for current 4, 5 and 7 Series machines
The bobbins for the B9 Hook hold 70% more thread than standard bobbins. This enables you to sew for even longer without interruption. Bernina 7-Series 710, 720, 740, 750, 770, 780, 790, Bernina 480, New Generation Series 500 535, 570, 590 (not earlier models)