A. G. Davis CIRCLE DIVIDER® and AA Gage ULTRADEX® tables feature a serrated-tooth (Hirth) coupling which is the fundamental design element engineered to provide exceptional accuracy, repeatability, rigidity and long life.

High accuracy and repeatability are achieved through the natural averaging effect of all teeth in meshed contact. The repeatability of any particular angular position is better than 1/10th the total accuracy band of the entire coupling.

The coupling is the final positioning device and is solely responsible for maintaining that faceplate orientation in all planes. Each coupling is designed with the highest possible coupling lock force and largest diameter to achieve maximum rigidity.

A.G. DAVIS CIRCLE DIVIDER® and ULTRADEX® tables maintain their accuracy indefinitely without any adjustments. The accuracy actually improves through normal use. This occurs because teeth have a natural tendency to conform to size, shape and pitch.