Silicon carbide, abrasive grain, grit size 400LG (lapping grade) is a lapping quality, or straight grade grit. Use straight grade grit for faster results when lapping. Other uses for the 400LG abrasive grit are for tumbling, sphere machines, drilling, faceting, etc. An order of one for the silicon carbide grit 400LG is one pound. Remember, the higher the grit number, the finer the grit.