Our most complete kit, the Master Installation Kit comes complete with everything youll need to rebuild the center section of your differential. These kits include the following, as needed per application: pinion and carrier bearings, pinion seal, pinion shims, pinion nut, crush sleeve or depth shims, ring gear bolts (most applications), o-ring, gear marking compound & brush, Loctite, cover gasket or silicone, carrier or super shims, slingers & baffle, and installation instructions.