The backset is the distance from the front of the lock to the centre of the spindle as shown above. If you intend to use new locks on an existing door, replacing your old ones, you will need to ensure the new lock fits into the existing hole in the door. To do this, measure the backset distance of your old lock. Our standard domestic locks are supplied with a 44mm backset length, but we can also supply locks with a backset of 57mm. Our commercial range of lockcases and latches come in either 57mm or 60mm backset. If you’re not sure get in touch with us and we’ll help specify the right thing!