Professional Diamond Selector II will indicate genuine diamond or fakeUses large / small switches for testing diamondsEmits audible sounds to easily differentiate the readingsMetal alert with continuous buzzing sound when user accidentally touches metal rather than stoneBatteries: 1 x 9v Battery (not included)Color: BlackSize: 6.5" x 1.625" x 1.875" / 16.3 x 4 x 2.2cm