Thread Check Inc. offers a full range of Master Setting Discs which are ideal for calibrating and setting comparators, snap gages and other precision measuring instruments. Master Setting discs are furnished with insulating grips to prevent heat distortion from handling. They are available in gagemaker tolerances from class XX thru class Z. Master setting discs are offered in high quality tool steel for longer gage life. They are available in 3 styles for various applications. Master setting discs conform to ANSI B47.1. They are ring lapped to size, and polished. Sizes are available up to 23 inches in style #3.