SC-7 7x Professional Measuring Magnifier Comparator adjustable diopter focus, has a precision ground corrected adjustable focus glass lenses and gives a dynamic image with metric linear scale and measures up to 15mm in 0.1mm increments. Clear base allows for easy external light flow in light conditions. Widely used for precision measuring, blueprinting parts, analyzing fractures, quality control, fingerprints, security papers, & print analysis. Comes in leather snapped storage case to keep optics protected..