US Patent 8348576 Fastener and fastener assembly with discontinuous threadform

The disclosure provides in one embodiment for a fastener comprising a cylindrical shaft, a head attached to the shaft, and two or more external longitudinal threadforms, where each threadform comprises a plurality of spaced protrusions forming a separate helical path around the shaft. When the shaft is inserted into a corresponding mating receptacle, a combination of the shaft and the mating receptacle provides two or more pitches. The disclosure further provides for a fastener assembly.