CRC 7mm Shim Set (20)

These fit on your SCX10 ii ring gear bearing to properly shim side to side movement. I find moving the ring gear to the furthermost position reference to the pinion gave me the smoothest operation. As the ring and pinion bed in you may have to revisit the shimming for best gear longevity. Most stock rings don't need shimming but as the ring wear in the pinion to ring gap will increase to the point where the force allows the pinion to move the ring away causing the tooth to skip possibly damaging the gear.