The basis of the Hellevation modular rear axle system starts with the highest quality 7075 billet aluminum axle machined for oversized 25mm (6205) bearings with roll formed M10 threads. 
 
The axle is integrated to the rails with interchangeable billet ends for a totally plug and play solution. Choose the axle ends needed to match your rail slot height.  1/2", 1", or 20mm rail slot axle ends are available.
 
Optionally you can create a 4 wheel setup by choosing the 4 wheel option which includes the outer wheel spacers.