The 250μm fibers 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 by polyethylene (PE)for cable with high fiber count,locates in the center of core as a metallic strength member.Tubes and possible fillers are stranded around the strength member into a compact and circular cable core.Aluminum tape is applied around the cable core,which is filled with the filling compound to protect it from water ingress.Then,the cable is sheathed by PE material as inner sheath.After wrapping of steel braiding,Finally,the cable is sheathed by PE sheath as outer sheath.
