The crack meter EDJ-40C (MTI.EWS.ER.M-EDJ-40C) is ideally suited for measuring the change in width of a surface crack to a resolution of 0.5 mm. It is integrated with a graduated scale and a transparent acrylic plate with a hairline cursor mark. The assembly when installed across the crack, the graduated scale and cursor move relative to each other depending upon the crack opening or closing.