GYTY53 (metal strengthening member, loose tube layer stranded filling type, polyethylene sheath, longitudinally wrapped corrugated steel tape armor, polyethylene sheathed outdoor optical fiber cable for communication) The structure of the optical cable is a single-mode or multi-mode optical fiber sheathed by a high-mode optical fiber The waterproof compound loose tube is filled with a large amount of plastic. The center of the cable core is a metal reinforced core. For some fiber optic cables, the metal reinforced core is also extruded with a layer of polyethylene (PE). The loose tube (and filling rope) is twisted around the central reinforcing core to form a compact and circular cable core, and the gaps in the cable core are filled with water blocking compounds. The cable core is extruded with a polyethylene inner sheath, and the double-sided plastic-coated steel tape is longitudinally wrapped and then extruded with the polyethylene sheath.