99.5% ceramic with high purity and high performance is a good material to be made into the shaft, sleeves/bushings/bushes with tight tolerances. Our compnay has made the ceramic industry standard in china and is a drafting unit. The tolerance of the outside diameter of the ceramic shaft/shafts can reach + -0.0075mm. There are three grades of ceramic to choose: 99.5% ceramic, 99% ceramic and 95% ceramic and the ceramic shaft/shafts have good abrasion, corrosion resistance and good surface finish.