Coaxial cable is a type of communications cable typically used by radio and cable companies. It carries radio frequency (RF) signal feeds from antennas and satellites downstream throughout their systems. It provides good reliability and redundancy because it carries the signal not only through the central wire, but through the separated metal jacketing, as well. Coaxial cable types differ by their Radio Guide (RG) designation, such as RG6 cable and RG59 cable. The lower RG numbers are characterized by heavier wire gauge, thicker insulation and better shielding for greater bandwidth and distance signal carriage. Products also vary by color, length, and other variables.