One of many greatest challenges throughout history is to see what can¬not be seen, to detect what is hidden, and to reap riches from these treasures. Actually, there are many ways to make a meter detectors, and this kit is one of these popular used ways to make a simple, but useful and heuristic, metal detector. This kit includes the basic components and PCB to help you make a metal detector, with the right soldering of these components, the detector can detect metal with a max distance of 5cm. It can be used to detect coins, weapons, knifes, etc, and also could be your best lesson of learning artificial circuit.