25X Measuring Microscope Pen is a pocket-sized microscope with measuring reticle for precision measurements. Is for inspecting defects and measuring conductor and pad widths, plated holes, and other tiny features and components on circuit boards. Field of view is 3.3 mm, with a scale division of 0.05 mm.

CircuitMedic, www.circuitmedic.com/parts/115-3115.shtml