Bernina 9 mm bobbin holds 70% more thread than standard bobbins. That means more sewing and fewer interruptions.

Compatible machines
B700 E, B 720, B 740, B 770 QE, B 790, B 790 PLUS
B 500 E, B 535, B 540, (new) B 570 QE,(new) B 590
B 435, B 475 QE, B 485, B 480