MT-RJ

An MT-RJ (Mechanical Transfer Registered Jack) connector is used to connect pairs of optical fibers. It uses a form factor and latch like the RJ-45 connectors, supports full duplex, has lower cost than ST or SC connectors, and is easier to terminate and install than ST or SC. Further, its smaller size allows twice the port density on a face plate than ST or SC connectors do.The MT-RJ connector was designed by AMP, but was later standardized as FOCIS 12 (Fiber Optic Connector Intermateability Standards) in EIA/TIA-604-12.

There are actually two different types of MT-RJ connectors — pinned and no-pin. The pinned variety, which have two small stainless steel guide pins on the face of the connector, are used in patch panels to mate with the no-pin connectors on MT-RJ patch cords.