Features: 1. The instrument can work continuously for a long time without heating or overload. 2. When the power supply voltage is lower than 6V, it will produce continuous squeaking, which means that the battery of the same type should be replaced if the power is insufficient. 3. The instrument has high sensitivity and can detect very small steel needle. 4. This instrument can detect broken needles on all wearing products such as knitting, clothing, shoes, socks and clothing. It can quickly and correctly find the broken steel needles that exist in the clothes to ensure the safety of personal wear. 5. This instrument can inspect ferromagnetic substances for foods materials. 6. This instrument can also check the presence of nails, steel bars and pipes inside wood, wall and tables. 7. This instrument can inspect the human body, livestock and other work injuries, knife wounds, crushing and other parts to see if there is any harmful iron residue inside. Specification: Item Type: Handheld Needle Detector Material: Plastic Power Supply: 6F22-9V battery, quiescent current: <5mA, dynamic current: 30mA Based on 1.5mmFe inspection block, the detection height can reach more than 10mm 0.7X20mm steel needle is the inspection basis, its detection height can reach more than 50mm Size: Approx. 135 x 65 x 35mm / 5.3 x 2.6 x 1.4in Package List: 1 x Handheld Needle Detector 2 x Battery Note: 1. The ambient temperature of the instrument is -5℃-40℃ 2. The power must be turned off in time after use to extend battery life. Please remove the battery in time when it is not used for a long time, so as to avoid damage caused by the battery being corroded by the components. 3. Pay attention to water proof, wet proof, and always keep it clean and dry. If it is damaged, the unit can be repaired for life. .