(Formerly "RS-422") An EIA serial line standard which specifies 4-wire, full-duplex, differential line, multi-drop communications. The mechanical connections for this interface are specified by EIA-449. The maximum cable length is 1200m. Maximum data rates are 10Mbps at 1.2m or 100Kbps at 1200m. EIA-422 cannot implement a truly multi-point communications network (such as with EIA-485), although only one driver can be connected to up to ten receivers. The best use of EIA-422 is probably in EIA-232 extension cords.