The device can be used in food, pharmaceutical, chemical,textile and garment, toy industry and so on, which is authorized by HACCP(food industry), GMP(pharmaceutical industry), and it can be applied for cookies, sauces, dumpling, hum, soup, candy, meat, frozen food, salted food, fast food, bakery etc, and other industries that have special requirements on detection sensitivity, anti-interference, waterproof. Besides, it can detect broken needles, metals mixed with products.