Ribbed idler kit for new style VMP 8 & 10-rib kits. Included with full 8 & 10-rib kit packages Includes: 76 mm ribbed billet aluminum idler pulley with black annodize and 6204-2RS bearing 20 mm ID ( VMP-76-10-20-RB) Idler standoff for front cover idler boss ( VMP-FSPC-20-8-10RB) M8 bolt with large washer (208186) This idler pulley is required for no-grind style FEAD when running the new style VMP 8&10-rib supercharger belt drive. Compatible with: Only works with new-style 8 and 10 rib kits that use the VMP/ATI balancers with a lip on each side of the supercharger drive pulley. VMP-918076 ATI/ VMP 20% OD 8-rib damper for 2020+ GT500 5.2 L & 5.0 L VMP-918075 ATI/ VMP 10% OD 8-rib damper for 2020+ GT500 5.2 L & 5.0 L VMP-918078 ATI/ VMP 20% OD 10-rib damper for 2020+ GT500 5.2 L & 5.0 L does not provide for correct belt alignment for older style 5%, 15%, and 25% OD kits.