The connector (Connector) and electrical appliance plug (Pin) of general electronic products are called plugs. Household AC power plugs and socket-outlets, having rod-like or copper-plate-like protruding male connectors, physically inserted into sockets

A slot or recessed female connector type power outlet.

Size is an important technical requirement related to whether plugs, sockets and converters can be used safely and meet universal interchangeability requirements to avoid misinsertion. Unqualified size will affect the user's use or cause poor contact,

Mis-insertion and other hidden dangers will cause damage to the equipment, and will cause fire and electric shock accidents.