1, no rust, acid and alkali, no special maintenance. 2, good wear resistance and long service life. Granite/Marble Platform.The "Xinxing" brand of granite measuring tools have the following characteristics: -High precision reliable stability resistant to deform and guanranteed accuracy under normal ambient temperature. -No-rust and anticorrosion. -Wear resistance long service life. -Any cutting or scraching for working surface does not bring about roughedgeswhich might influence its measuring precision. -Non magnetization -Glossy surface without sluggishiness when the workpieces or tools are moving on it. CNC components made of black granite,include base,column,beam and railway,with a maximum of6000mm*3500mm*600mm. All the standard size are in store and the special size can be made as your requirement.