Check the listing for details. 3/32 Silicon Nitride Diff Balls - 3/32 Differential Balls Ceramic Grade 5. Condition: New. Listed at 11.99 USD. 3/32 Silicon Nitride Balls super precision diamond polished Grade 5 from World Champions ACER Racing. 12 pieces. The only thing harder than our Ceramic Balls are diamonds. That’s one reason why diamonds are used to polish them. They are impervious to chemicals and oxidation. At 79% lighter than Tungsten Carbide yet even stronger than tungsten carbide, these Grade 5 diamond polished ceramic balls provide the absolute lowest in rotational mass for superior performance and durability. Not only that, but these balls lower the coefficient of thermal expansion. This leads to consistent concentricity and smoothness even with increased temperatures. Our silicon nitride balls have a melting temperature of 2552 F! Made from pure Silicon Nitride (Si3N4) material: NOT ceramic coated steel. Each pack is matched to ensure consistent concentricity, roundness, and smoothness among the balls. Our silicon nitride balls are so strong, they will not shatter or melt under even the most extreme racing conditions FREE SHIPPING