What Is It?A replacement centre case for the Lockmaster / Milamaster door lock. If you're having problems with your door lock, the gearbox is the most likely culprit and changing it is as simple as removing a few screws.Tech Details :Important measurements: 35mm Backset / 92mm/62mm PZ CentresThis is the mechanism inside the door that is operated by the handle.Most likely to be the problem when a lock fails.Reversible latch for left or right handed doorsDouble Spindle - for lever/ lever & lever/pad operationWe also have a technical drawing in our images if you do need more information.