Battery: 9V battery(not included) Convenient for carrying. Convenient Tester Tool - LED light and audio indicate testing result, easily differentiate the readings Non-destructive testing - Do not hurt your item. automatically alarm if the battery is too low. Professional Gemstone Selector - This gemstone testing equipment is not only a diamond tester, but also a multi gemstone tester. can detect if a gemstone is real or fake, including: diamond, sapphire, ruby, crystal, , jadeite, and other precious stone of various sizes. Colour: silver-gray Material: plastic Size: 135 x 40 x 22mm Package Contents: 2 x Tester Pen 2 x drill floor 2 x Chinese and English manual 2 x leather case Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.