Ribbon cables are usually specified by two numbers: the spacing or spacing of conductors, and the number or method of conductors. A pitch of 0.050 inches is the most common pitch, but finer and courser pitch cables are also available, from 0.025 inches to 0.156 inches, and the pitch can be customized according to specific applications. In some portable electronic devices, cables with a pitch as low as 0.3 mm can be found.
Due to the availability of standard connectors, the number of wires or paths is usually limited to a few values. These include 4, 6, 8, 9, 10, 14, 15, 16, 18, 20, 24, 25, 26, 34, 37, 40, 50, 60, 64 and 80. The wires used in ribbon cables are usually stranded copper wires, ranging in size from 18 AWG to 34 AWG or smaller.