This part of IEC 60603 covers 8-way, shielded, free and fixed connectors, references dimensional, mechanical, electrical and environmental characteristics and tests in IEC 60603-7 and IEC 60603-7-1, and specifies electrical transmission requirements for frequencies up to 100 MHz. These connectors are typically used as category 5 connectors in class D cabling systems specified in ISO/IEC 11801. These connectors are intermateable and interoperable with other IEC 60603-7 series connectors as defined in Clause 2 of IEC 60603-7. These connectors are backward compatible with other IEC 60603-7 series connectors. NOTE Transmission performance categories: in this IEC standard, the term "category", when used in reference to transmission performance, refers to those categories defined by ISO/IEC 11801.