The Model 1800 is the original and most popular counterfeit detection device in the world with over 200,000 units sold. Using state-of-the-art technology, the 1800 verifies the magnetic properties of the ink on the face of all U.S. Dollars in order to verify the authenticity of a note. Genuine notes are identified by a green light while suspect notes are identified with a red light and audible tone. The 1800 is compact, lightweight, and portable. The unit can be powered by the 110/220 switchable power supply (included) or on six "AA" batteries. The 1800 comes with a 1 year parts and labor warranty and is upgradeable for future releases of U.S. Currency.