1. Products of enterprises with high reputation, stable quality and good after-sales service should be selected.
2. First check whether the logo and logo of the purchased product are complete (including the product's implementation standards, grades, manufacturer's name, address, production date). Whether the package is firm, the contents of the manual are consistent with the product, and the caution is exaggerated. The facts do not match the phenomenon.
3. Observe the appearance quality of the product, including the lock head, lock body, lock tongue, handle and cover plate parts and related accessories. Is the surface color of the plated parts and painted parts bright and uniform, with or without signs of rust and oxidation? And damage.
4. Check whether the function of the product is reliable and flexible. Two or more products should be selected for comparison check. Especially when purchasing the two-way lock product, all the keys must be used to test the inner and outer locks separately. You should also check the insurance organization of the product. It is recommended to try each lock at least three times.
5, then check the key of the key, such as five spoon teeth, each key should have not less than three different key teeth, while the first and fifth teeth should try not to choose the deepest key, to facilitate the key The insertion and removal is not easy to break.