The most common electrical connector used for conventional lighting fixtures. Also known as "stagepin," "2P&G," "slip," "Bates," and "GSP." The first pin connectors were made by Kliegl Bros. in the 1920s. In the 1930s, Union Connector made the connector for Bates Electric in Hollywood. Although the 20amp version is most common, 60amp and 100amp versions are available, and primarily used in the film/video industry. For a 20A-2P&G Stage Pin Connector: Hot = Black wire = pin (or socket) farthest away from middle pin Neutral = White wire = pin (or socket) nearest the middle pin Safety Ground = Green wire = pin (or socket) in the middle (identified by "GR" in the photos below) It is important to note that the 60A and 100A have a different wiring configuration than the 20A version. 20A Male Stage Pin Connector unassembled: For discussion, see the threads http://www.controlbooth.com/forums/lighting/614-installation-stage-pin-plug-cable-plus-history.html, and http://www.controlbooth.com/forums/lighting/6597-crimp-connector-crimper.html. See also the Collaborative Article: http://www.controlbooth.com/forums/collaborative-articles/13565-connectors-stage-pin.html.