Intuitive Design, Fast and Safe - Our diamond tester features an LCD display and LED indicators for clear and accurate test results. Designed for fast, precise, and safe diamond testing, it ensures no damage to the gemstone during operation. Delivers reliable results consistently, making it a popular choice among professionals, hobbyists, collectors, and business owners. A practical and thoughtful gift option. Easily Test - Simple one-button operation with clear visual feedback. No prior experience required. The diamond test pen is user-friendly: simply turn it on, gently place the tip on the gemstone, and wait for the audible beep to determine authenticity. For genuine diamonds, the indicator lights illuminate accordingly and a sound signal is emitted. Non-responsive readings indicate the stone is likely imitation, such as cubic zirconia. Key Operation, Easy to Use - Position the pen tip vertically and lightly on the surface of the gemstone. Adjust the carat setting using the up/down buttons according to the size of the gem. There is no need to input the exact carat weight. For diamonds of 1.0 carat, one green light will illuminate; for 0.5 carats, two green lights; for smaller gems (such as small cuts or melee), three to four green lights should be selected. Avoid touching any buttons during testing to prevent interference. High-Frequency Sound During Metal Testing - A high-frequency sound may occur when testing metal due to the thermal conductivity principle used by the device to differentiate diamonds from simulants. Since certain metals conduct heat similarly to diamonds, this response is normal and expected. [Warm Reminder]: Always follow proper testing procedures. Do not use the device on unsuitable materials such as metal, skin, or wet surfaces to ensure accurate results. Incorrect usage may affect performance. Select the appropriate carat range before testing to avoid inaccurate readings. [Hand Contact Requirement]: During testing, maintain contact with the touch panel located on the back of the device. Failure to do so may result in incorrect readings. [Error Indication]: If an error occurs, the device may flash or power off automatically. This typically happens when testing non-gemstone materials such as metal or skin. Color: As Shown Material: Plastic Package Contents: 1 x Diamond Test Pen 1 x 1M USB Cable 1 x Test Platform Note: Light reflection and differences in display screens may cause slight variations between the product color in images and the actual item. Measurement tolerance: ±1–3 cm.