30X 6 LED Glass Optical Lens Full Metal Folding Bedding Tester Magnifier Magnifier Magnifier MagnifierSpecifications:Material: Metal, double-layer glass optical lens. Product Multiplier: 30X Standard Product Net Weight: 165g Product Package Weight: 195g Product Size: 60*52*51mm/2.36*2.05*2.01"Package Size: 70*65*62mm/2.76*2.56*2.44" Packing: Leather Case, White Box. Principle: To see the details of a small object, move the object close to the eye to increase the viewing angle and form a larger image on the retina. But when the object is too close to the eye, you can't see clearly. In other words, to be aware of the truth, not only should the object have a large enough angle to the eye, but it should also occupy the right distance. Of course, for the eyes, these two requirements are mutually restrictive. If a convex lens is placed in front of the eyes, this problem can be solved. A convex lens is the simplest magnifying glass, which is a simple optical device to help the eyes observe small objects or details. Usage:Observation method 1: leave the magnifying glass close to the object to be observed, and keep the distance between the human eye and the object being observed unchanged. Then move the handheld magnifier back and forth between the subject and the human eye until the image is large and clear. Observation method 2: magnifying glass as close to the eyes as possible. The magnifying glass does not move by moving objects until the image is large and clear. Goal:1. An achromatic lens without chromatic aberration can observe photos very clearly and identify gemstones. It has a packing box and is easy to carry.2. It can also be used for jewelry certification test, substrate surface quality, color correction and other inspections. Notes:1. Due to the different monitor and light effect, the actual color of the item may be slightly different from the color showed on the pictures. Thank you!2. Please allow slight measurement deviation due to manual measurement. 1 XLup