After using push-pull doors and windows for a period of time, check the chute to ensure the smooth and flexible opening and closing of italian aluminum windows.  

When the door lock does not work, you can add the right amount of pencil core foam and other lubrication materials to the keyhole for lubrication, not random injection of oil, because the oil is easy to absorb ash, cycle after cycle, will only be more convenient to open the other lock.