down. In Europe, Hong Kong, Malaysia, Singapore, and India this type is near-universal, and toggle style switches would be considered old-fashioned. Australian rocker switches In Australia and New Zealand, a small rocker switch is almost universally used, in the form of a switch mechanism, which is mounted from behind into a wall-plate—attaching via mounting lugs, as shown in the photo on the left. A slightly larger "cover plate", supplied with the wall-plate, or additional to it, then clips over the assembly, as an additional insulating barrier covering the deep set wall-plate mounting screws - which are "deep set" to prevent inadvertent human contact. The "cover plate" can be removed without the use of tools, such as when wall painting is required. While larger "decorator" style switches are readily available in Australia, the advantage of the smaller mechanisms is that wall-plates are available to mount from one to six individual switch mechanisms, or other correspondingly sized "mechanisms" - such as dimmers and indicator lights - in the same space as one (or two) switches of larger design could be mounted. Since the mechanisms are small, they can also be mounted into "architrave" plates, for mounting in positions where it is not possible to mount a "standard" sized wall-plate. An example is shown in the picture below on the right. All of the switch mechanisms have no exposed metal parts requiring grounding (earthing). While switches, wall-plates, and cover plates from different manufacturers tend not to be interchangeable, switch mechanisms of this type have been available in Australia since 1951. The keystone module system for extra-low voltage electrical jacks (patented in 1975) is somewhat similar in appearance to these modules, but the design of the keystone mountings are different, and keystone modules can be removed without a tool. (A similar system, but with bigger switches, is used in Italy.) As shown in the disassembly photo, the switch actuator pivots in two holes in the sides of the plastic switch body. An actuator bar slides in two grooves inside the actuator, pressed down by a compression spring into a notch in the common contact bar. The common contact bar is free to rock on a small diameter rod, welded to the common terminal. However, because of the pressure applied by the compression spring, the common contact bar will always be held against one of the two contacts. When the actuator is moved, mechanical energy