Rubber ball to open and close any type of screwed case back
Diameter: 2.6" or 67 mm
Non marring, will not harm your metal case back
For hobbyist and professional watchmakers
Inexpensive, easy-to-use large contact area case opening rubber ball allows most watch case backs to be opened and will not leave marks, or mar your metal. Inflated Rubber ball to open and close all types of screw-down case backs. This rubber ball allows you to use your hand to control the opening and closing of your watch case back.