Granite surface plate is base on the quality of underground rock, after one hundred      million years of natural aging,form is stable.Wear resistance, acid resistance, alkali resistance,    high corrosion resistance, never rust. Granite surface plate precision is very good..

Granite surface plate is made of high quality natural marble stone after machining,lapping by hand and become.Black luster, precision uniform texture, good stability.Strength and high hardness.

Granite surface plate is made of natural stone material precision measuring tools,the instruments and meters, precision instruments, mechanical parts inspection, all is the ideal       datum.