Various functions of mortise lever door lock provide you a wide of variety of choices. Compared with the torsion spring in the lock body of the traditional door locks, our locks adopt the compression spring structure, which can bear the frequency of locking/unlocking up to tens of millions of times. All the locks undergo various tests in accordance with Japanese JIS standards, including 96-hour salt spray test, acid and alkali resistance test, adhesion test after water boiling and hardness test to ensure the durability of appearance. OEM mortise lever lock orders are welcome.