Working Voltage:DC3-5V,Detecting Distance:Less than 60mm Metal detector is a high performance metal sensor designed for security.It can also apply to game entertainment,car detection,equipment position detection,metal proximity switch, statistics,etc.. Buzzer to ring and the red light indicator is on when the metal is to the metal detector. Easy to install by PCB silk screen and component listing,and we also PDF instruction at this page.Simple circuit is easy to and your soldering skills during assembly process.It is really a funny welding practice for solder beginners color:blue material:plastic Package Contents: 1 * Simple Metal Detector Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.