GYTC8Y [Outdoor Optical Cable for Communication with Metal Strengthening Member, Loose-Sheath Stranded Filling, Polyethylene Outer Sheath] The structure of the optical cable is to insert single-mode or multi-mode optical fiber into a loose tube made of high-modulus plastic and filled with waterproof compound. Among them, the center of the cable core is a metal strength member. For some fiber optic cables, the metal center strength member is extruded with a layer of polyethylene. The loose tube (and filling rope) is twisted around the central strength member to form a compact and round cable core. The gap in the cable core is filled with water-blocking compound and an outer polyethylene sheath is extruded, and a steel strand sling is added to form a cable.