QA 3 Pin Plug - 5A

5 Amp 3 Pin Plugs (part of the BS 546 family) like their smaller 2 Amp counterpart, though used quite rarely these days are for connecting low power appliances - usually table lamps, free standing lamps and such like - to a centrally switched lighting circuit which can optionally have a dimmer control allowing dimming of all lamps on that circuit together. Hotels are an example of where you might find this kind of arrangement. Though once used for theatre and stage lighting applications, apart from schools where you might still find them, the larger 15 Amp variety have become the standard.