The transport rings, like the stargates, were the technology of the Ancients and the Ori, later stolen by the Goa'uld. They function similarly to stargates, transmitting a matter stream over shorter distances, for example between a planet and a ship in orbit. Transport rings can transmit across space, under water, and through solid matter, however there is a limit to their ability to make a connection, and penetration deep underground or through a mile of solid ice is not possible without modification to the matter stream transmitter. When activated, a set of five rings appears and a beam of light dematerializes any matter within them, either living or non-living, and transports it to another destination where it is rematerialized. The rings are by-directional, and it is possible for matter to be transmitted in both directions simultaneously.
Ring sets are designed to operate in pairs, each ring mechanism using sensors that can locate other rings and detect the coordinates to make a connection. Because rings seek a connection, it is possible for a third set of rings on a ship, for example, to intercept a matter stream during transmission. When the controls are set a certain way, the rings seek out the nearest set of rings, even if the rings are aboard a cloaked ship. At close distances, within approximately five meters, the rings can also function independently without the need for a set of receiving rings to make a connection. The Ori have been known to deposit a portable ring platform on a planet so that the rings aboard an Ori warship can be used even if no corresponding platform is available on the planet. When engaged in mid-flight without a set of receiving rings, the rings will transmit an object only a few meters and attempt to rematerialize the object again in midair.
Found on teltacs, alkesh, and motherships, and within most Goa'uld, Ancient, and Ori facilities, the rings are powered by crystals, similar to those used in the DHD or hyperdrive engines, which are found both under the segments of the ring platform and in the control device. The ring platforms are fairly standard in size, with the platform mass estimated at 12.9 metric tons, and up to approximately 6 to 8 people can comfortably use the rings at a time. The rings can be activated either by a six-button control panel or by a device worn on the wrist, usually in conjunction with the ribbon device. The technology has been incorporated into the design of the Prometheus and the Odyssey, which also use a set of transport rings.
First Introduced: Children of the Gods
Significant Episode Reference: Jolinar's Memories, The Devil You Know, Tangent, The Serpent's Venom, Fail Safe, Descent, The Other Guys, Memento, Evolution, Lost City, Avalon, Flesh and Blood, Insiders, Line in the Sand, Bounty