Most scopes are designated first by a few numbers, like "4x 32mm", or "3-9x 40mm", or "3-12x 40mm".
The first number or number range is the amplification of the range of "power", where "6x" or "6 power" represents a target of more than six times. "3-9x" or "3-20x" will represent variable power, such as zoom lens on camera. The final number refers to the lens or target of the objective of the objective lens (in millimeters). The smaller objective lens makes the lens easy and easy to operate; A larger person gathers more light to get a brighter vision, especially in low light conditions.