1, first, see whether the surface of the lock is smooth, smooth, low quality door lock usually rough surface, potholes, there are obvious defects, and the surface coating is very easy leg color.
2, then, carefully check the door locks in the packaging of the accessories are complete, feel comfortable, usually inferior door locks mostly from the family small workshop, a long time side will be a problem.
3, to see whether the product has passed the national quality inspection department's testing, usually the technical indicators of poor quality door locks can not meet the national standards.
Finally, warn the consumer, in the purchase of the lock, do not look at the appearance and try to buy a lock at the time of purchase (open), and careful inspection and repeated tests after the purchase. If you buy the poor quality and material lock, it will cause you a lot of trouble, light you close in the house, heavy damage to life and property, the correct choice of the function and quality of the door lock will give you the convenience and safety.