Cutex (TM) Brand 10 Juki Sewing Machine M Size Aluminum Bobbins with Slot #107-23609 Pack of 10 Aluminum Bobbins With Bobbin Winder Slot For Juki Industrial Walking Foot Machines. Juki part # : 107-23609 (10723609) Bobbin Measurement : 1" wide X 3/8" tall With slot for bobbin winder.