... C.High hardness advanced Ceramic sealing Ring, ceramic insulation rings, zirconia ceramic rings 3. Alumina Ceramic Sealing Rings Alumina (Al2O3) is a hard, chemically resistant ... include the ceramic plunger, ceramic plunger pump, ceramic rod, ceramic shaft, ceramic piston, ceramic water valve sheet, ceramic pipe sleeve, ceramic loom plunger, ceramic seal ring, special shape ceramic, ceramic knife ...