Here’s what SKIRT NUT® is:
Skirt Nut® is a heavy duty Grade 10 safety flange nut for M22 studs, exceeding all applicable standards of SAE J1965.  The “skirt” penetrates the stud holes in the disc wheel. It delivers more thread engagement for better torque-holding ability in the SAE established torque range of 370 – 500 ft/lbs.
Skirt Nut photo
Example of clocking
Skirt Nut's ability to hold torque within the approved range prevents movement of the wheel under the flange washer, eliminating vibrations, self-loosening flange nuts and potential "wheel off" situations.
Shown above right is a new wheel with properly torqued flange nuts, already beginning to clock after less than 5,000 miles.  Note the rust and galling marks around the washer, a sure indication of unsafe movement.  This bolted joint is on its way to failure.
Legal info: Copyright, Use of, etc.
See how Skirt Nut® compares to old-style flange nuts:
Safety Trigo. Inc.
70 Ward Road, Unit B, Brampton, Ontario, Canada  L6S 4L5 
TEL  905-867-9891      TEL/FAX  519-968-2523