Stereo zoom microscope Stemi 355, Mat ESD (KIT 3), bino, w.d. 110mm, 10x/23, 5,5:1 , 7,2x-40x, AL, RL C LED

This refers to the magnification factor of a single microscope lens. A lens with the number 40 is referred to as a scale of 1:40 or simply a factor of 40 times. If you multiply the lens factor by the eyepiece factor, you get the magnification.

The light source illuminates the object and is available in various forms.