Replacement differential case set designed to refresh worn or damaged differential housings in compatible ARRMA RC vehicles. The set uses a tough composite case reinforced with a molded-in steel insert and precision metal cross shaft inserts to improve durability under load and rough driving conditions. Precision screw threads and included hardware make servicing and reassembly straightforward. This kit restores the differential housing and sealing surfaces so internal gears and components operate smoothly and reliably.