In addition to lock plug, hardware fittings quality is also important. The material of lock is aluminum alloy, stainless steel and copper, among which the strength and durability of aluminum alloy is the worst, while the copper is the best but the price is the highest. The workmanship and quality of each brand is greatly different, which the average consumer is difficult to distinguish. If the consumers want to buy the "lock", the only way is to compare various locks, big brand products are very sophisticated, while low-end locks will seem rough. In addition, good lock has a very crisp sound during opening, while most low-end locks in the key insert will appear to be loose and open sound is much more depressing.
Generally after years of using, lock plug will naturally wear, which is easy to be opened by tooth-form keys. Ordinary locks plug should be changed after five or six years using. A lot of community security doors and locks are purchased and installed by real estate developers and mostly is not particularly good quality locks. "Mass use of the same type of lock in the same neighborhood, in theory, the risk of "a lock to open several doors" will increase. Many new residents say that they often enter the wrong unit, open the door only to find that is not their home. If don't change the lock for a long time, it can produce more serious security problem.