The pinless moisture meter detects relative moisture levels caused by leaks and flooding, and measures the moisture content in your building materials. The MT28 Moisture Meter utilizes an electromagnetic field to penetrate a depth of ≤20mm. The hold function freezes the data, features a three-color display, and includes a sound alarm. Please keep a safe distance from metal objects while taking measurements. Press and hold the calibration button for at least 5 seconds. Auto off after 30 minutes, and a 9V battery is included., Weight: 0.32628414776 Pounds, Manufacturer: SHENZHEN REDDRAGON INSTRUMENTS CO.,LTD