Gauge is an equipment to measure and
test the size of product by using assigned sizes (length, angle).

There is a limit gauge to test if the size of a product is within the limit and an indicating gauge to measure the deviation degree from the standard measure of the product by changing the measuring range.

There is also a standard gauge to be used as a standard and a limit gauge to be used for a designer to pass the product within the preassigned tolerance when to fabricate a machinery.