The Aickar Digital Caliper is made from stainless steel and includes a depth measurement probe as well as precision ground jaws. It is protected with IP Grade 54, which blocks out water splashes, insects, and dust that may affect the accuracy of the caliper. It is ideal for both professional and home use and it is designed to allow you to measure from zero at any point on the scale. Conversion between millimeters/inches/fractions is easily achieved at the touch of a button. The calipers can be used for internal, external, step and depth measurements and come complete with a machine grooved thumb roller for accurate positioning.