Operation method: 1. Turn on the power, the power indicator lights up, the instrument starts to warm up, and the instrument can be used after a few seconds. 2. Put the bare drill to be tested into the appropriate concave hole of the support tray, with the table top facing up. The inlaid person does not need to put it in the tray hole, but can hold it by hand. 3. Light up several LEDs according to the weight of the real and fake diamonds to be tested and the temperature of the measurement location. 4. Remove the probe sheath, hold the instrument and touch the back cover of the instrument with the index finger of the right hand; make the probe vertically and lightly contact the table of the real and fake diamonds to be tested. 5. Carefully watch the reflection of the instrument, if the remaining yellow light-emitting diodes light up, when the light reaches 9 diodes, and the buzzer sounds, it means that the tested person is a real diamond. On the contrary, if there are less than 9 lights on and the instrument does not make a sharp sound, it means fake diamonds or imitations. Precautions: The surface of the test object is clean, flat and dry. Don't wear gloves. Don't detect metal. Best to measure in no wind conditions. The operating temperature is within the range of 5-35 degrees Celsius, and the humidity is below 80%. When testing diamond, your right index finger must keep touching the metal panel on the back of the tester. Please turn off the power after the test to save power. Test Result Analysis: If lights >= 9 and have sounds, it is true diamond. If lights <9 and no sounds, it is not diamond. If lights is 7 or 8, it is true crystal. If lights is 6 or 7, it is true jade. If lights is 4 or 5, it is glass. Don't test metal,Don't wear gloves.

?NOTICE? * When testing, the probe needle and the tested object must be at a 90° angle. * When testing diamond, your right index finger must keep touching the metal panel on the back of the tester, while you do not touch the panel if you test other gemstones. * Do Not test any metal. * Don't wear gloves. ?Portable electronic device for distinguishing real diamonds from other simulated stones. LCD displays & LED indicators. Uses switches for testing diamonds, Emits audible sounds to easily differentiate the readings. ?Using the principle of difference of thermal conductivity between diamond and fake diamond, detect and distinguish colorless diamond and imitation in 2 seconds. ?This gemstone tester pen is designed to detect if a diamond or gemstone is real or fake, If stone is Fake crystal, a simulant such as cubic zirconium ( CZ ), will be no reaction. ?The diamond Tester Pen is simple to operate to get results. Real Diamond will emit sounds and lights >=9. It is designed for quick, precise, and safe diamond testing.

Batteries required: No. Best Sellers Rank: #171,145 in Arts, Crafts & Sewing. Customer Reviews: 4.1 out of 5 stars 214 ratings 4.1 out of 5 stars. Item model number: NCElec. : B07RPY9SXN. Item Weight: 2.75 ounces. Package Dimensions: 6.46 x 2.6 x 1.3 inches.