Voltage/Metal/Wood Detector - Multi-use metal joist and Wood Stud Detector.Voltage/Metal/Wood Detector features include: Stud Detector Finds wood or metal studs and joists behind walls, floors, and ceilings Detects wood up to 3/4&rdquo: Detects 90-250V within 6&rdquo: of a hot unshielded wire Auto calibration stud detection 4 LED&rsquo:s visual and audio indicators Wood Stud Detector is operated by one 9V battery (not included) Order Qty of 1 = 1 Piece Below is more info on our Voltage/Metal/Wood Detector