When used as a networking medium, unshielded twisted-pair (UTP) cabling consists of four pairs of color-coded wires that have been twisted together and then encased in a flexible plastic sheath. Network UTP cable has four pairs of either 22- or 24-gauge copper wire. A UTP cable has an external diameter of approximately 0.43 cm (0.17 inches), and its small size can be advantageous during installation.

UTP cable does not use shielding to counter the effects of EMI and RFI. Instead, cable designers have discovered that they can limit the negative effect of crosstalk by:

UTP cable relies solely on the cancellation effect produced by the twisted wire pairs to limit signal degradation and effectively provide self-shielding for wire pairs within the network media.