Relates to dial gauges with the plunger movement parallel to the plane of the dial. It applies to gauges having dial diameters from 1 7/8 inch to 2 1/2 inch, as measured from the outside of the scale marks, and scale divisions of 0.001 inch (sometimes sub-divided into half divisions of 0.0005 inch, in which case they are commonly designated '0.0005 inch gauges), 0.0001 inch or 0.01 mm.