Features WITH INDICATOR; The diamond test pen has 2 kinds of sound and 3 kinds of color light display, the test result is clear at a glance, clear and intuitive. WORKING PRINCIPLE: Differentiate between real and fake diamonds by measuring the thermal conductivity of diamonds, with good practicability. EASY OPERATION: Turn on the power, the power indicator lights up, the instrument begins to warm up, and the detector can be used after a few seconds. HIGH ACCURACY: This diamond selector supports non destructive testing, with high accuracy and sensitivity, ensuring accurate measurement results. PORTABLE DESIGN: The diamond detector is small and compact, easy to hold, can be used anytime, anywhere, suitable for long term measurement work. Specification: Item Type: Diamond Tester Material: Plastic Size: Approx. 13.5 x 4 x 2cm / 5.3 x 1.6 x 0.8in Package List:1 x Diamond Tester Package List 1 x Diamond Tester