The strong magnet searches iron bar: For searching the iron in the cloth products. When the products pass by the iron-search needle, if iron is found inside, so long as disassemble a little mouth to insert the super-strong magnet, and mix, search for and absorb, the iron will be magnetized soon.
The watch, instrument, magcard don't want to close to magnet and the in order to prevent results in damage.
The magnet iron easily ground crack, the attention avoids bumping shot and need not hour puts on to protect a set.
Can't adsorb color metals.