An item consisting of electrical conductors separated from each other by a continuous homogeneous dielectric (including porous types and touching and/or interlocking beads or spacers), and designed primarily for the conduction of radio frequency energy. Includes a single conductor inclosed in an outer concentric conductor (coaxial) with or without a protective sheath; two or more coaxial cables laid parallel with an outer electrical shield and/or common sheath; two or more parallel conductors with an outer electrical shield and/or a common sheath; two or more individually insulated twisted conductors with or without an electrical shield and/or protective covering. All types have low-loss or special characteristics at high frequencies. Refers to bulk quantities only; for items of definite length with processed ends or terminated in fittings, see CABLE ASSEMBLY, RADIO FREQUENCY. See also LINE, RADIO FREQUENCY TRANSMISSION.