This part of IEC 61076 is a detail specification for two-part rectangular connectors. This detail specification covers mechanical and environmental requirements, and electrical transmission requirements for frequencies up to 3 000 MHz. These connector s transmission requirements are specifically intended for specific pairs of contacts, which are isolated from the other pairs of contacts, such as by means of individual pair shields within the connector. These connectors are similar to, intermateable with, and intended to be used with IEC 60603 7 series connectors. The IEC 60603-7 series connectors are typically used in ISO/IEC 11801-1 balanced cabling systems. The ISO/IEC 11801 balanced cabling systems are organized by categories according to frequency range and by basic cabling component types, e.g. according to shielding configurations. A primary common feature among the IEC 60603-7 series connectors is backward compatibility to lower frequency categories. IEC 61076-3-110 series connectors are backward compatible with IEC 60603-7-7, IEC 60603-7-71 and IEC 60603-7-82 connectors. IEC 61076-3-110 series connectors are not backward compatible with some IEC 60603-7 series connectors.