Umbilical Cables are the electrical power cables used to link Evangelions in the field to external power supplies in Tokyo-3. The connectors attaching to the rear of an Evangelion are visually similar to a three-point plug. Two large holes in the connector allow a retro-rocket to slow its descent and prevent damage when it is discarded.
Tokyo-3 has a multitude of power buildings that house connectors and cable for an Evangelion to switch to a new cable, in case the old cable has reached its maximum length or been severed. A portable version of the umbilical cable is seen in use in Episode 08, being set on the deck of an aircraft carrier and drawing power from the ship's reactor.
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