layer will rust if it falls off, and the lock will be useless in less than a month.

Second, to look at stability, mainly manifested in the lock cylinder, key and lock body, the lock cylinder with less bullet eyes, it is easy to be opened, a skilled locksmith or thief, with a simple tool can be opened in a few seconds, then we live inside, stability and privacy are not guaranteed, how dangerous. At present, most domestic manufacturers produce such low-end products. Whether the mutual opening rate of the lock cylinder is qualified or not, the mutual opening rate refers to the percentage of the number of times the lock is opened and the number of test openings. If the lock cylinder mutual opening rate is high, then hundreds of households in large communities install door locks uniformly, and the keys between neighbors may open each other, which is quite convenient but the stability coefficient is greatly reduced. We can distinguish from the tooth flower of the key, the more tooth flowers, the better, less than 0 tooth flower lock cylinder must not be bought, the lock body to buy more insurance, double tongue or multi-tongue kind, buy single tongue to buy explosive, so that the thief is difficult to open, not to say that it is a thief, let's say that we, if it is the kind of single tongue, can be opened with ID cards, bank cards, because it only has an oblique tongue, no insurance, but the explosive monoclinic tongue stability performance is much higher.

Third, the smooth and beautiful appearance of the door lock is related to the owner's face, can not be ignored, you can pay attention to the following points when purchasing: 1. Whether the surface of the lock body is smooth and there are no defects that affect the aesthetics.2. Whether the key is smooth and smooth.3. The key can be inserted into the lock cylinder hole to open the door lock to see whether it is smooth and flexible.

The fourth thing to look at is to look at the stubness of the lock, and the lateral static tension of the handle is an important indicator of the firmness of the lock. An excellent lock. Its handle should ensure that it switches a million times and still is straight and does not sag.