First, the good copper wire toughness is very good. Take out a copper wire bent a few times, if it is easy to be broken then proves that this product is very bad. And the surface of the copper wire will usually have a thin layer of plastic skin, there will be no flame lit high-quality copper wire surface.

Second, the wire core, if the wire core cable is central to illustrate the better the quality of the copper wire. If not in the middle, so it is easy to appear when electricity consumption is too large a breakdown of safety accidents.

Third, when buying copper wire should pay attention to check the fine copper wire length error and error of the diameter of the cross section line. This is very important, the general length error is greater than 5%, shows that the copper wire must have been bad small workshops to move hands and feet.