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,traffic statistics,etc.. Buzzer start to ring and the red light indicator is on when the metal is close to the metal detector. Easy to install by PCB silk screen and component listing,and we also provide PDF instruction at this page.Simple circuit is easy to assemble and train 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 shooting 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.