In the illustrative embodiments, the reinforcing layer is approximately 0.1 to 0.125 mm (0.004-0.005) thick and approximately 0.023 to 0.3 mm (0.009-0.012) wide, and is wound from uniaxially oriented flat monofilament spun from materials including polyethylene terephthalate, polybutylene terephthalate, polypropylene, nylon, and other polyesters.