QandA

The origins of our large plugs go back to the end of World War Two. With so many houses to build after the war, and facing a chronic copper shortage, Britain was keen to find a way of wiring homes that used less cable. Previously, each mains socket had its own connection to the fuse board. To save copper, Britain adopted the ring main system, with sockets connected sequentially, but this meant each connection needed its own fuse. Instead of putting the fuses in the sockets, they were included in the plugs themselves. Hence the UK's bigger plugs. Answered by Gareth Mitchell

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