This Strummer full ceramic cartridge / deep-groove ball bearing has high speed, heat resistance, hardness, and corrosion resistance.
Material Differences
White Ceramic: Material ZrO2 (Zirconium Dioxide): Stronger against alkaline conditions (high pH)
Black Color: Material Si3N4 (Silicon Nitride): Stronger against acidic conditions (low pH), lower thermal expansion coefficient (smaller expansion at high temperatures).