Highly Sensitive Hand Held Metal Detector For Airports Railway Stations Security Check Features: Imported low temperature IC and the latest circuit design to achieve the most complete functionality with the smallest size Advanced push and pull button design, the one-button operation can realize the conversion between sound and light and mute/vibration operation The 9V battery is reduced to about 7V, with constant detection distance and power saving, which can be used for more than 20 hours continuously Humanized push-pull battery cover design makes it easy for customers to replace the battery without any tools. Eco-friendly and with fire retardant materials, moisture-proof and dust-proof design Can simultaneously detect magnetic and non-magnetic metal, and with excellent detection sensitivity on copper and aluminum materials too. Three indication by light: power normally on (green), alarm light (red), battery power is in undervoltage state (yellow). With charging port, plug and charge, convenience charge at any time Specification: Voltage: 7-9 v Power : 270mW Operating frequency: 22 KHZ Working current: <50 mA Operating temperature: -5 to 55 ℃ Power supply:1* 9V laminated battery (not included) The highest sensitivity: * General phone: 20 cm * Small tools: 15 cm * One-dollar coins: 10 cm Size: 38*7.8*3cm/15*3.1*1.2in Weight: Approx.286g/10.1oz Package list: 1 x Hand-Held Metal Detector (battery not included)