This billet idler pulley is identical to the Metco Motorsports MIP-90 idler pulley except that is 10mm larger. The larger size is designed for use in auxiliary idler applications where a smaller than stock supercharger pulley is installed. This pulley is CNC-machined from billet aluminum and black hard-coat anodized on the belt surface and back side for long-lasting surface protection. A heavy-duty bearing is precision-fit into the center section, and a snap-ring ensures everything stays in place. The kit includes a billet bearing cover and a stainless steel socket head fastener to mount this idler pulley to the original or Metco Motorsports pulley mount.