Bulk Coaxial Cable
Coaxial cable is a cable that has an inner conductor which is copper and layered with an insulating dielectric; which then is surrounded by a tubular conducting shield and an outer insulating jacket. Introduced and patented in 1880 by Oliver Heaviside, coaxial cables are used as a transmission line for cable television signals, computer network connections and radio frequency signals. The main advantage of coaxial cables over other types is the electromagnetic field that carries a signal exists only between the inner and outer conductors. Bottom line is that you can install coaxial cables next to metal such as gutters and not experience any external electromagnetic interference.