The structure of GYTZA53 optical cable is to put 250µm optical fiber into a loose tube made of high modulus material, and the loose tube is filled with waterproof compound. The center of the cable core is a metal reinforcement core. For optical cables with certain cores, a layer of polyethylene (PE) needs to be extruded outside the metal reinforcement core. The loose tube and filling rope are twisted around the central reinforcement core to form a compact and round cable core, and the gaps in the cable core are filled with water-blocking fillers. After the plastic-coated aluminum tape (APL) is longitudinally wrapped, a polyethylene inner sheath is extruded, and after the double-sided plastic-coated steel tape (PSP) is longitudinally wrapped, a flame-retardant outer sheath is extruded to form the cable.