Principle: To see the details of a small object clearly, it is necessary to bring the object closer to the eye, thereby increasing the visual angle and forming a larger image on the retina. However, when the object is too close, it becomes difficult to focus and appears blurry. Therefore, clear vision requires both sufficient angular size and an appropriate viewing distance. These two factors are naturally limited by the eye's focusing ability. By placing a convex lens in front of the eye, this limitation can be overcome. A convex lens acts as a simple magnifying glass, serving as a basic optical tool to assist in observing small objects or fine details.Magnification: 10X Color: Black Material: Plastic Size: 41 x 44 x 45mm Lens Diameter: 20mm Package Contents: 1 x Scale Magnifier Note: Light and different display settings may cause slight variations in the color of the item compared to the actual product. Measurement error allowance is +/- 1-3cm.