These are usually fitted on or recessed into the stone at the side of the door, the pull knob being mounted on a flat brass backplate or recessed into a cup- shaped backplate. Wires running in conduits built into the internal plaster with cranked junctions operate the bell.
A metal plunger operated by foot may be found on the third step down below pavement level. Some houses were also provided with bell pulls beside the garden gate.
It is still possible to have the bell-wire system repaired or renovated, but where an electrical system is preferred, the original manually operated pull can be retained and converted to operate a switch.
Very often bell pull knobs have been replaced by bell pushes, retaining the backplate. A similar system of wires and levers was used to open gates for access to basement areas.