摘要 |
A fastener having a retaining member with a top portion and an elongated hub extending downwardly from the top portion. A helical groove extends throughout a substantial portion of the length of the hub and the upper end of the helical groove is formed to change the lead between the upper end of the helical groove and at least the uppermost loop of a helical coil mounted in the helical groove to create a tensile load on the hub by a helical coil having at least the uppermost loop located in the helical groove. A helical coil with a plurality of loops has at least the uppermost loop located in the helical groove in the hub, and the end portion of the uppermost loop contacts the portion of the groove formed to change the lead to create a tensile load on the hub to mount the helical coil on the hub.
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