PAMANTOGEL The contact terminal set screws are installed at a slight angle to allow easier screwdriver access after the switch mechanism has been installed into a wall-plate - before fixing the wall-plate to the wall. Also shown is a "loop" connection terminal. This terminal plays no part in the action of the switch but, because there is available space, it is provided as an insulated terminal for joining other wires, if required (such as the neutral wires).|London (IMechE): Professional Engineering Publishing Ltd