lts main material is bayer alumina, which is electrically fused in high temperature, being added with the right quantity of oxidized chromium. lt is pink. lts hardness is close to, but toughness higher than that of WA. The abrasive tools made of it feature excellent durability and high processing cleanness, which are suitable for the precision grinding of the measuring tools, lathe main shafts, instruments and apparatus parts, threading work pieces and samplers, etc.