The structure of GYTA 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 reinforced core. For some fiber optic cables, a layer of polyethylene (PE) needs to be extruded outside the metal reinforced core. The loose tube (and filler rope) is twisted around the central reinforcing core into a compact and round cable core, and the gaps in the cable core are filled with water blocking filler. The plastic-coated aluminum tape (APL) is longitudinally wrapped and then extruded into a cable with a polyethylene sheath.

8 and 12 represent 8 cores and 12 cores

B1 represents that the G.652 type is a conventional single-mode fiber.

Communication fiber is divided into six categories and several sub-categories: G.651, G.652, G.653, G.654, G.655 and G.656

(1) Class G.651 is a multimode fiber, and IEC and GB/T are further subdivided into four subclasses A1a, A1b, A1c and A1d according to their core diameter, cladding diameter, and numerical aperture parameters.

(2) The G.652 category is a conventional single-mode fiber, which is currently divided into four subcategories: G.652A, G.652B, G.652C and G.652D. IEC and GB/T name G.652C as B1.3 , the rest are named B1.1

(3) G.653 fiber is a dispersion-shifted single-mode fiber. IEC and GB/T classify G.653 fiber as B2-type fiber.

(4) G.654 fiber is cut-off wavelength shifted single-mode fiber, also known as 1550nm fiber with the best performance. IEC and GB/T classify G.654 fiber as B1.2 fiber.

(5) The G.655 fiber is a non-zero dispersion-shifted single-mode fiber. It is currently divided into three subclasses: G.655A, G.655B and G.655C. IEC and GB/T classify the G.655 fiber as B4. optical fiber.