This Sony Triax Cable is a triaxial type of electrical cable similar to coaxial cable, but with the addition of an extra layer of insulation and a second conducting sheath. It provides greater bandwidth and better rejection of interference than coaxial cable. The 3/8" thickness of this cable allows it to be used over extended distances, up to 2296' (700 m).
It is most commonly used in the television industry as a connecting cable between a camera and its CCU.