Shortened Fastener With Locally Controlled Thread Height

A male anti-cross threading fastener comprising:

• a substantially round shank having a lead end, a torque end, and a plurality of male threads around a circumference of the shank, the plurality of male threads comprising:
• a standard thread around at least a portion of the circumference of the shank and having a standard thread contour defined by troughs at a minimum diameter, a flat crest at a major diameter, and flat flanks from the troughs to the crest having a width at a pitch diameter and a thread angle of about sixty degrees, wherein the major diameter of the standard thread is between a lower major diameter limit and a higher major diameter limit;
• a transitional thread forming a continuous helix with the standard thread around at least a portion of the circumference of the shank and comprising a transitional thread contour defined by troughs, a flat crest, and flat flanks from the troughs to the crest and a thread angle of about sixty degrees and a height no higher than the lower major diameter limit of the standard thread contour, wherein the wherein the transitional thread winds less than about five-eighths of a turn (225 degrees) around the shank;
• and
• an anti-cross thread forming a continuous helix with the transitional thread around at least a portion of the circumference of the shank and having an anti-cross thread contour comprising an outside diameter approximately the same as the pitch diameter of the standard thread, and wherein the anti-cross thread contour comprises a shape defined by a curve extending from a curve at a trough to about the outer diameter,
• wherein the transitional thread contour has a crest that widens as the height transitions from the lower major diameter limit of the standard thread to the outside diameter of the anti-cross thread.