Z – External cablesZKS – External duct cablesW – Internal cablesZW – External/internal cablesS – External, self-supporting cables Symbol Meanings for Outer Sheath Materials X – Polyethylene Y – PVC Q – Polyurethane V – Polyamide Yn – Flame-retardant PVC N – LSOH material. Z – External cablesZKS – External duct cablesW – Internal cablesZW – External/internal cablesS – External, self-supporting cables Symbol Meanings for Outer Sheath Materials X – Polyethylene Y – PVC Q – Polyurethane V – Polyamide Yn – Flame-retardant PVC N – LSOH material. A TOSLINK optical fiber cable with a clear jacket. These cables are used mainly for digital audio connections between devices. A fiber-optic cable, also known as an optical-fiber cable, is an assembly similar to an electrical cable but containing one or more optical fibers that are used to carry. An optical fiber, or optical fibre, is a flexible glass or plastic fiber that can transmit light from one end to the other. Where traditional copper cables max out at about 10 gigabits per second, fiber optic cables can handle 100 gigabits per second with commercially available hardware, and. Data transfer and telecommunications have been transformed by optical fiber technology. It consists of tiny glass or plastic fibers that can carry data as light pulses. The fiber which is used for optical communication is waveguides made of. Optical cables are often described as the backbone of modern communication, yet many buyers still approach them with uncertainty. That difference alone creates hesitation.