MD4030 Underground Metal Detector, Measuring Range: 1-30cm Features: 1. Two operating modes: all-metal mode, recognition mode 2. Volume adjustment: adjust the volume of speakers and headphones 3. Headphone interface: you can connect the headset to use (not provided) 4. Pointer display: The pointer will swing with the discovery of metal 5. Waterproof detection disk: metal detector can be used in shallow water 6. Adjustable lever: adjust the length of the metal detector Application: 1. Search for metal objects buried underground. You can find coins, ruins, jewelry, gold and silver ornaments everywhere. Widely used in security inspection, outdoor treasure hunt, metal inspection, etc. Specifications: 1. Power supply: 2 x 9V (6F22) (without battery) 2. Frequency: 5.0KHz 3. Current: 10mA static, up to 70mA 4. Voltage: 7.2-9.6V 5. Sensitivity: US 25 Cent: 130mm 6. Display mode: mechanical pointer mode, sound mode 7. Telescopic length: 30.7-42.5 inches 8. Probe diameter: 7.87 inches