Nexx Racing's Optional/Replacement Differential Ceramic BALL BEARINGS, The hardest, smoothest, longest lasting, most consistent balls, Size: 3/32. Pieces: 10. Material: Ceramic. Replacement balls to keep your differential in top, working condition. ALWAYS good to have spares for maintenance or replacements. for NX-126 & NX-185 Ball diffs. (also fits most other popular diffs) NX-152 differential pressure plates recommended for best results.)