MCN 0.5X MECHANIC Auxiliary Objective Stereo Microscope Lens For A Stereo Mobile Repairing Microscope. Magnification: The 0.5X indicates that this lens reduces the magnification by 0.5 times compared to the microscope's standard lens. Working Distance: The "WD 165" means the lens provides a working distance of 165mm. This is the distance between the lens and the object being viewed. Purpose: The lens is designed to be used with trinocular microscopes, which are commonly used for mobile phone repairs and other detailed work. It allows for a wider field of view and increases the working distance, making it easier to manipulate small objects under the microscope. Additional Function: It can also be used to increase the working distance. Compatibility: It is compatible with stereo microscopes, trinocular microscopes, and binocular microscopes. Materials: Typically made of optical glass for clear imaging.