Because of its immunity to electronic interference and its greater speeds over longer distances, fiber optic cabling has become the conduit of choice for high-speed network communications. This is a "Yellow" single-mode cable with a 9µm core and 125µm cladding diameter. The cable has a pair of color-coded ST connectors on each end. The cable jacket is OFNR (Optical Fiber, Nonconductive, Riser) rated by UL, which means that it complies with fire safety and insurance requirements and is safe for use within the walls, and between the floors, of commercial class buildings.