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 and chemical materials. specification: 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 and chemical 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. : Condition: Item Type: Handheld Needle Detector Material: Plastic Power Supply: 6F22-9V battery, quiescent current: