In a traditional microscope, the magnification is calculated by multiplying the objective magnification by eyepiece magnification. With a microscope where the eyepiece is replaced with an imaging chip and digital display, magnification is calculated in a slightly different manner. The first factor is still the objective magnification. The second factor now depends on the imaging chip resolution and the LCD image scale.
The objective will directly enlarge the size of the specimen by its magnification. So a 4x objective will create a 4mm image of a 1mm specimen on the imaging chip.
For these LCD digital microscopes, the factor depending on the imaging chip and LCD is 10. So this factor acts like the eyepiece magnification for this kind of microscope. The final magnification on the display versus the actual size of the specimen is just the objective magnification times 10.