【Easy to View】: Clear and easy-to-read analog dials that can distinguish various types of gemstones without waiting for testing, including: diamonds, sapphires, rubies, crystals, and more. 【Diamond Tester】: Green indicator will be showed if the stone is a real diamond. It will make continuous buzzing sound when user accidentally touches metal rather than stone. 【Easy to Use】: The diamond test pen is used for fast, precise and safe diamond testing. And it comes with an instruction manual, so even a novice can use it more easily, packed in a PU box. 【Jewelry Gold Testing】: This gemstone detecting device is not only a diamond detector, but also a multi-gemstone detector. It can detect if a gemstone is real or fake. Designed to provide fast and accurate results. 【Complete Packaging】: The box includes all kinds of measuring tools you need to buy diamonds, as well as various testing tools, so that you can monitor at any time.