Cat8 is the highest copper class, certified to 2000 MHz under ISO/IEC 11801 Class I/II, carrying 25GBASE-T and 40GBASE-T over a restricted 30 metre channel. That distance limit means it is designed not for horizontal cabling but for the top-of-rack and end-of-row runs that connect a server cabinet to the switch above it in a data centre. Its fully screened S/FTP construction and heavy conductor gauge call for more careful planning of bend radius and in-cabinet cable management.