LED light and audio result indication. Red light will be displayed and audio indicator sounds if the stone is a real diamond. Simple calibration for stones of different sizes. Accurate and reliable reading. Light weight, matched with a convenient carrying case. Detailed user manual included in the package. The thermal conductivity meter is designed and manufactured according to the thermal conductivity of diamond. It is specially used to identify real and fake diamond. Tips: Gemstones should be clean, dry and at room temperature. During the test, transferred to the first or second grid. V2 Gold Test Kit with Gemstone Pen, Handheld Electronic Diamond Tester with LED for Diamonds, Sapphires, Rubies, Crystal, Agate, Jade, Gems, Hardness Testing Tool Features: Easy to use. LED light and audio result indication. Red light displays and audio indicator sounds if the stone is a real diamond. Simple calibration for stones of different sizes. Precise and reliable reading. Corresponds to a test platform for loose stones. Light weight, matched with a convenient carrying case. A detailed user manual is included in the package. Features: Color: black. Power supply: 1 DC 9 V battery (not included). Dimensions: 16 x 4 x 2.2 cm. Maintenance and repair: 1. The instrument is very sensitive to the probe, should be particularly careful to protect, do not use should be placed on the sheath. 2. The preparation of the indicator light is very dark, indicates that the battery will be exhausted, should be replaced in a timely manner. 3. The instrument is not used for a long time, please remove the battery. 4, in order to accurately detect, the correction proposed once a year. Tips: The thermal conductivity meter 1 is designed and manufactured according to the thermal conductivity of diamond. It is specially used to identify real and fake diamond. 2 instruments for precision electronic instruments, the use of the environment for 5-35 degrees Celsius, the relative air humidity at 80 percent . 3 stones must be clean, dry and at room temperature. 4 When testing, transfer to the first or second grid. Content: 1 Diamond Selector II.