configuration the plastic material just outside the crosshead will generally conform to the shape of the annulus 99 as illustrated in fig6 as depicted in that figure the multiple wire strand 10 is coated by a corrosion inhibitor 11 which generally has an overall circular shape the plastic jacket just outside the die is discontinuous and includes a generally circular portion 101 and integral flap 102 formed by the opening 90 in the die the integral flap 102 overlaps at least a portion of the other end of the plastic material so that a seal can be formed between the plastic material downstream in the performance of the process the plastic jacket is pulled or drawn down by the moving coated strand to form a jacket for the tendon pressure is applied to the overlapping flap 102 by rollers 50 and 52 to utilize the heat of the plastic material from the extrusion process in order to form a seam or seal between the flap 102 and the underlying plastic material rollers 50 and 52 can be stationarily mounted or mounted such that the rollers are permitted to move a limited vertical amount under a biasing pressure in order to accommodate the naturally occurring fluctuating movement of the tendon in the manufacturing process yet to provide a proper pressure on the flap 102 to achieve a desired seal the rollers should preferably include an arc to generally conform to the outer surface of the tendon as illustrated in dashed lines in fig6 as illustrated in fig1 the rollers 50 and 52 are preferably mounted in the region.