Product Description:Precision Circle Cutter - 1/2" - 24" Diameter range. 6 wheel turret head. Powerful suction cup to hold glass in place while in use. Free-wheeling ball handle for positive pressure on score.
The Tarheel Precision Circle Cutter is marked in centimeters and millimeters, so you would need to use the metric system as your starting point when converting to standard measurements.