Build your very own treasure finding device with the 4M Metal Detector Robot. Learn about mechanics and assemble a working device that sends alarms at the detection of unseen metal artifacts above or beneath the surface. Your friends will be amazed. Hunt for buried treasure on the beach or your back yard by driving the robot back and forth with the remote control. When you hear it beep, you have found something metallic. The metal detector unit is detachable and usable as a hand-held metal detector.