The Micro FM123 lens has four switchable lenses, 0.78x, 1.56x, 2.34x and 3.12x, located in the unit. Simply rotate the head to switch between magnifications. It includes a 10x eyepiece which allows you to use the lens as a monocular microscope with magnification of 7.8x, 15.6x, 23.4x and 31.2x. Using a 13 CCD camera and a 19 screen, the on screen magnification is about 62x, 125x, 188x and 250x subject to 4:3 aspect ratio of both screen and camera chip. For other aspect ratio such as 16:9, these magnifications may change depending on the screen and the camera used. Ideal for high magnification field of view measurement.