Description30 Optical Glass Lens 6 LED Full Metal Foldable Line Tester Loupe Magnifier Thread Counter Magnifying GlassSpecificationsMaterial metal, doublelayer optical glass lens.Product magnification 30 standardProduct net weight 165gProduct packaging weight 195 gProduct size 605251mm2.362.052.01Package size 706562mm2.762.562.44Packaging leather case, white cardboard.PrincipleTo see the details of a small object, it is necessary to 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, it cannot see clearly. In other words, to be aware of the truth, not only should the object have a sufficiently large angle to the eye, but also take the appropriate distance.Obviously, these two requirements are mutually restrictive for the eyes. If a conve lens is placed in front of the eyes, this problem can be solved. Conve lens is the simplest magnifying glass, which is a simple optical instrument to help the eyes observe small objects or details.Method of useObservation method 1 Keep the magnifying glass close to the object to be observed and keep the distance between the human eye and the object to be observed unchanged. Then move the handheld magnifying glass back and forth between the object 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, move objects until the image is large and clear.Purpose1. An achromatic lens without chromatic aberration can observe images and identify gemstones very clearly. It has a packaging bo and is easy to carry.2. It can also be used for jewelry certification testing, substrate surface quality, color correction and other checks.Notes1. Due to the different monitor and light effect, the actual color of the item may be slightly different from the color shown on the pictures. Thank you2. Please allow slight measurement deviation due to manual measurement.1 Magnifying glass005f