... airports, industrial zones, government buildings, schools, hospitals, etc. hand-held metal detector MD-200 Features:1. Operating frequency:2. Weight: 272g3 ... . LED light proves: LED red warning indicator lamp,LED green insufficient indicator lamp, voltage indicator lamp LED battery of power 8. Battery: 9V ... ): 40mm h) Lead brick (1g): 30mm High Sensitivity Hand-held Metal Detector MD-200