Abstract: A theft prevention assembly for use with car wheels and the like includes a threaded sleeve adapted to be threaded onto a wheel mounting stud in place of the usual lug nut, the sleeve having an enlarged head portion at its outer end which is loosely encircled by a ring. The ring and enlarged head portion having opposed surfaces preventing the ring from moving outwardly of the head portion. A special wrenching tool has clamping members between which the ring and outer end of the sleeve may be clamped to produce sufficient frictional force to cause the assembly to rotate as a unit when the wrench is turned.