The keys of the apartment doors do not close, do not touch, the doors hit the frame, etc. It cured with one shot. Since there is no explanation of usage, it is ok if you check on site and do not mistake the direction of lever. It seems that there are many times that the hinge bends by hitting the dolly against the door. Until now I removed the door and fixed the bending. Heavy doors were difficult to install alone. If you have this, you will be cured in 1 minute. Convenient. Necessary items are heavy for the owner of the building, but it is cheap shopping to think of calling a craftsman to be sturdy and lifelong repairing. I will recommend it.