Verify diamonds quickly and accurately with this Professional Diamond Tester Pen. Designed for jewelers, collectors, and anyone buying or selling jewelry, this portable tester provides fast gemstone identification using a precision probe. LED indicators and an audible alert make results easy to interpret, while the lightweight pen-style design allows for convenient everyday use. Simply power the device with a 9V battery (not included), allow it to warm up, and gently touch the probe to the stone for rapid testing.