This gemstone testing equipment functions as both a diamond tester and a multi-gemstone tester. It can detect whether a gemstone is genuine or synthetic, including diamond, sapphire, ruby, crystal, jadeite, and other precious stones of various sizes. - If the number of lights is 9 or higher and it beeps, the diamond is genuine. - If the number of lights is around 9 and it beeps, the sapphire is genuine. - If the number is between 6.5 and 7, the gemstone is genuine. - If the number is between 7 and 8, the crystal is genuine. - If the number is between 6 and 7, the jade is genuine. Before testing: 1. Insert the battery into the tester. 2. Remove the probe cap. 3. Turn on the switch. 4. Ensure only one light illuminates on the scale. 5. Confirm the "ready lamp" is lit. 6. For diamond testing, set the light number according to the indoor temperature and diamond weight. 7. For other gemstones, calibrate the probe by placing it vertically on a glass surface, adjust the light to 5, then proceed with testing. Power supply: 9V battery (battery not included) Features: Large and small switches for diamond testing Color: Black Material: PC + metal Dimensions: 16 x 4 x 2 cm Package Contents: 1 x Diamond Tester 1 x Testing Platform 1 x Carrying Case 1 x User Manual 1 x Packing Box Notice: When testing any gemstone, the probe needle must be positioned at a 90-degree angle to the object. During diamond testing, keep your right index finger in contact with the metal panel on the back of the tester. Do not press the panel when testing other gemstones. Avoid testing on metal surfaces. Do not wear gloves during use. The package includes only the items listed above; other accessories are not included. Note: Lighting and display differences may cause slight variations in the color of the item shown in images compared to the actual product. Measurement may vary by 13 cm.