[6 kinds of shapes whetstones] Product shape: knife-edge, semicircle, diamond, triangular, rectangular, cylindrical,meet your different polishing needs ,good Hardness, abrasive sharp, good thermal conductivity [Green Silicon Carbide-High-temperature forging Material] Green carbon oil stone (Pleace Note: Green silicon carbide whetstone texture is slightly softer) ) and it’s not easy to fall off high-temperature calcination, high temperature resistance and corrosion resistance. NOTE: Prices may vary by product model and material.