A handy instrument that instantly verifies the authenticity of diamonds based on their thermal properties. Powered by 3 AAA alkaline batteries. The Presidium Diamond Mate Tester tests for diamonds with the signature Presidium retractable probe tip that ensures consistent pressure against the gemstone during testing for more reliable results. With the industry’s thinnest probe tip size of 0.6mm, PDMT tests for diamonds as small as 0.02ct. Test results are instantly indicated by an LED light and continuous audible beep. Powered by 3 AAA batteries. A rechargeable version (Presidium Diamond Mate C) is also available. Product comes with 1-year warranty. Product can be powered by 3 AAA batteries or by optional Universal Power Adaptor accessory connected to external power source. Ships from the USA