The VMP 100mm idler pulley uses a heavy duty NSK bearing. A spacer is included for use on 2011+ 5.0L Mustangs with the Roush or Whipple/FRPP supercharger kits. The idler goes on the bracket that is bolted to the passenger side cylinder head. It is easily swapped out by taking the tension off the belt.
Note: Fits 11-16 5.0L Mustang with TVS blower, a small amount of grinding is required, recommended for pulleys 69mm and smaller.