This is the longest wheel stud available for the Classic Mini- 3.125" (78mm). It should only be used when running 3/4" or larger wheel spacers in special applications. Note that these will NOT fit most front disk brake cars and are intended primarily for use on the rear with wide rear drums AND wheel spacers.
3.125" is length of shaft, not including the head. Threaded portion approx. 1.125"
All wheel studs used on the Mini are 3/8" diameter with 24 Thread per inch.