Simple and easy to use, this set is used to test gold from 9 to 24 karat (9K, 10K, 12K, 16K, 20K, 22K, and 24K). Distinguishes gold plate from solid cold and tests all colored gold alloys. Non-destructive on pieces. Determines platinum. Automatic shut-off increases battery life. Tests within seconds. Simply add a few drops of the solution to the small testing "dish". Attach the alligator clip on the unit to the piece of jewelry being tested. Dip the piece into the solution. The unit will then light up and indicate the karat value. Please see the included operation manual for more detailed instructions! Includes Testing Solution No. 1995, cotton swabs, an eraser, and a water-based varnish pencil. Made in the U.S.A.Please contact us with any questions. Thanks for looking!