Product Features With a highly compact design, this diamond tester can perform fast, accurate and safe diamond testing, making it ideal to take with you when buying diamonds. This diamond tester will indicate whether your diamond is real or fake. You can quickly and easily understand diamond data. This diamond tester's LED lights and audio indicate the true and false results of the test diamond. This diamond tester is a precision electronic instrument, the operating environment is 5-35 degrees Celsius, and the relative air humidity is 80%. Gemstones to be tested must be clean, dry and at room temperature. The tester is non-destructive and easy to operate. Maintenance and Repair: 1. The instrument is very sensitive to the probe and must be protected with special care, and should be covered with a sheath when not in use. 2. When the indicator light turns dark, it means that the battery is about to be exhausted, and the battery should be replaced in time. 3. If the instrument is not used for a long time, please remove the battery. 4. For accurate detection, it is recommended to calibrate once a year. Specifications: Color: Black Power: 1 x DC 9V battery (not included) Item size: 16 x 4 x 2.2cm (6.6 x 1.6 x 0.8in) Package Contents: 1 x Diamond Selector II Tester 1 x Protective Leather Case 1 x SMS Platform 1 x User Manual