This group brings together the three classes that form the backbone of horizontal cabling: Cat6 is certified to 250 MHz and carries 10GBASE-T to roughly 55 metres, Cat6E works with a wider margin as an intermediate class, and Cat6A guarantees 10 Gbps across a full 100 metres at 500 MHz. U/UTP construction is sufficient in less dense environments, while U/MRTP and screened designs are preferred in tightly bundled channels where alien crosstalk is a risk. The LS0H jacket is mandatory on in-building routes that require low smoke and halogen-free emission in a fire.