The fibers, 250um, are positioned in a loose tube made of a high modulus plastic. The tubes are filled with a water resistant filling compound. A steel wire, sometimes sheathed with PE for cable with high fiber count, locates in the center of core as a metallic strength member. Tubes (and fillers) are stranded around the strength member into a compact and circular cable core. The PSP is longitudinally applied over the cable core, which is filled with the filling compound to protect it from water ingress. The cable is completed with a PE sheath.
Standard: YD/T 901-2001, IEC60794-1 

Product characteristics                                                                                

1. 2~228 fibers, jelly filled, fiber contained loose tubes 

2. Good mechanical and temperature performance
3. High strength loose tube that is hydrolysis resistant
4. Special tube filling compound ensure a critical protection of fiber
5. Specially designed compact structure is good at preventing loose tubes from shrinking
6. Crush resistance and flexibility
7. PE sheath protects cable from ultraviolet radiation
8. Good cable watertight.