Aven 26800C-541 Shop Pocket Microscope, LED Illumination, 40x Magnification, 4mm Field of View Handheld shop-type microscope for specimen examination in the engineering, tool making, quality control (QC) inspection, field research, gemology, and medical industries Focus wheel for detailed examination with pointed accuracy for inspection of small areas and objects Magnification ability of 40X, with 4.0 mm field of view (FOV) Built-in LED illumination with ability to be switched on and off Built-in scale with 0.05 mm graduations