The most trusted and sought after colored gemstone tester has been redesigned with the user in mind to be more compact, sturdy and portable. The Presidium Gem Tester II (PGT II) features a clear and direct analog display for a quick way to identify diamonds/moissanite and separate up to 15 common colored gemstones from one another based on their thermal conductivity. It still features a retractable probe tip that ensures consistent pressure against the gemstone during test resulting in more reliable results. With the industry’s thinnest probe tip size of 0.6mm, the PGT II tests gemstones as small as 0.02ct. Coated gemstones can also generally be tested with the PGT II. Note: Does not differentiate between natural and synthetic colored gemstones or diamonds against moissanite. Features: Detachable probe pen with retractable thermoelectric probe tip that ensures constant pressure between probe and gemstone. Industry's thinnest probe tip (0.6mm) for testing gemstones as small as 0.02ct. Metal alert buzzer to ensure that probe tip is in contact with gemstone during testing. Clear and easy-to-read analog dial. Can differentiate between 15 types of gemstones. Built-in glass and simulant test discs for reference. Benefits: Identifies diamonds/moissanite and most colored gemstones. Tests both polished and unpolished gemstones. Tests gemstones as small as 0.02ct. Consistent and reliable results every time. No waiting time between tests. Simple and easy to use. Runs on 2AA batteries or adaptor.