Jack plug - or socket - Is a socket and plug combination used in CONSUMER audio goods and equipment (for example ipods and PSP headphone sockets).

It is usually (and sometimes also called) 3.5mm (millimetre) or 2.5mm - depending on the diameter of the barrel of the plug used. (3.5 is much more common).

The connector is not considered professional and is replaced by the XLR connector in professional camera and audio equipment.