Features 1. Good material: Made of sturdy and durable ABS shell, high sensitivity alloy probe, rubber protective cap, and thermal conductivity plate. 2. Fast and Accurate Measurement - A fast, accurate, and safe method to distinguish diamonds from simulated objects without causing harm to diamonds. 3. Easy to use: Turn on the power, wait for the heating to be ready, hold it (place your finger on the heat transfer plate), and use the probe to make 90 degree contact with the tested object. 4. A thermal conductivity meter is an electronic instrument designed and manufactured specifically to distinguish the authenticity of diamonds based on their thermal conductivity performance. 5. This instrument is a precision electronic instrument, with a usage environment of 5-35 degrees Celsius and a relative humidity of 80% in the air. The tested gemstones must be clean, dry, and at room temperature. (The product does not come with a battery) Specification Pocket and portable handheld Non destructive testing, easy and accurate operation Working power supply: DC9V battery External dimensions: 16 x 4 x 2.2cm Weight: approximately 130g Material: Plastic Color: Black Package weight: 150 g Package Include: 1x Diamond Tester Test Pen