1.2 billion carats annual procuct capacity of synthetic diamond makes us the largest manufacturer in the world. Our diamond coucludes several series: HHD,HWD,HFD,etc. HFD also called fine grain diamond mesh size from 80 to 400. And HHD,HWD are different for the different color, synthesizing technology,classification and TI,TTI gap. We have the most advanced TI,TTI test machines so that we can assure our customer the best quality.