Use this chart to help find the industry “size” of your pocket watch. Measure the diameter of the movement with a digital gauge. This will only work on ROUND pocket watch movements. – do not use the measurements of the dial or outside case.

Example: if you have a 14.40 mm pocket watch movement, you would call it a 19/0sĀ  pronounced “NinteenĀ ott” size.

To download a PDF version click here.