The Mitutoyo 530 series vernier caliper has two sets of jaws and a depth bar for four-way measurement in inch and metric units of outside dimension (OD), inside dimension (ID), step and depth, for use in applications where the highest amount of accuracy is required—for instance, in scientific research. The caliper has a dual vernier scale with an upper scale that measure in inches and a lower scale that measures in millimeters. A 14-degree vernier face angle improves the visibility and prevents parallax error in measurement of readings. It is also equipped with a depth measuring blade that has rounded edges to make accurate measurements. The scales are raised to slide easily and protect the graduation markings from degrading. A thumbwheel permits fast and easy measuring. A clamping screw on the upper scale rotates to control scale movement and locks to hold the sliding jaw's position. It is best used in applications that require measuring an object to its lowest decimal point.