The fibers, 250μm, are positioned in a loose tube made of high modulus plastic. The tubes are filled with a water-resistant filling compound . A steel wire, sometimes sheathed with polyethylene(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. Characteristics:1.Good mechanical and temperature performance;2.High strength loose tube that is hydrolysis resistant;3.Special tube filling compound ensure a critical protection of fiber