FIG. 1 shows a cross-sectional view of an article of the invention wherein an axially-oriented core 1 is surrounded by a layer 3 of porous expanded PTFE. The core 1 is a tensile strength member which is preferably comprised of porous expanded PTFE but may also be comprised of other materials such as glass or carbon fibers, polycarbonate, polysulfone, polyphenol, polyamide, polyimide, polyamide imi