[Simple and fast] Diamond tester pen is designed for fast, accurate and safe diamond testing. In just a few seconds, even a novice can immediately distinguish real diamonds from other simulated gems. [Easy to use] Diamond tester is easy to use, with LED lights and audio indicators. Just place the tip of the diamond tester gently on the gemstone. If the gemstone tested is a diamond, the pen will beep and display a row of fully lit LED lights. If the gem is crystal or zirconia, the tester will not beep. [Easy to carry] Diamond detector and 60X LED loupe are both light and compact, and both are equipped with a carrying bag. They can be placed in your wallet or backpack without taking up a lot of space. They are a must-have kit when going to a garage sale, market, swap meet, etc. [Magnification] The package also contains a 60X LED loupe. It can help examine the details of diamonds, and can also be used for coins, reading, inspection, etc. [Wide range of use] Jewelry diamond testers have a wide range of uses, not only for testing diamonds, but also for industry, circuit boards, printing, gardening, identification, education, geography, homes and offices. Color: black. Material: metal. Package contents: 1 set x diamond tester. Only the above package content is included; other products are not included. Note: Light and different displays may cause the color of the item to appear slightly different from the real thing. Measurement allowed error is +/- 1-3 cm.