Precision tooling ball used as a reference point for critical inspection, layout, and machining operations. Adjustable type has no shoulder, so it can be set at any desired height then locked with a setscrew. Concentricity between ball and shank is .0002″ TIR. These Construction Balls are available with 1/4, 3/8, and 1/2″ ball sizes. The 1/2″ ball size is shown here, and is available in several shank diameters and lengths. Made in USA.