Stud Sensor Accuracy +/- 5 mm Overall Height 1 1/2 in Batteries Required Batteries Required (Included) Overall Width 3 9/16 in Materials Detected Ferrous Metal Live Wire Wood Battery Type 9V Scan Depth for Ferrous Metal - Maximum 1 1/2 in Scan Depth for Wood - Maximum 1 1/2 in Scan Depth for Live Wire - Maximum 2 in Features Auto Calibration Ergonomic Design and Soft Grip Buttons Marking Channel Helps Improve Accuracy of Marking-Out Readings