When buying a lock, be sure to observe the quality of the lock. Generally, the copper lock core key is plugged and unplugged freely, and the lock of the poor quality is not the same. When installing the lock cylinder, it must be suitable, can not reverse the card, or can not easily lock and unlock, this time carefully check to eliminate the fault. In the process of use, if the lock is found to be unsuitable, do not pour the oil into the lock cylinder. After a long time, the lock core will be stuck by the dust, and the spring will not work normally, causing the lock cylinder to not open. If your lock is not working well, you should use gasoline to wash it off and remove the dust inside. This will have a great effect. The key can be inserted and removed freely, and it will extend the life of the lock.