Raw material is made of epoxy resin, quartz powder, catalysts, pigments and other fixatives and, after a few high-temperature baking, top to bottom, from the inside to the outside of the same material as a whole, one through the core, stability is evenly without bubbles. Normal state stereolithography, never deformation, density of up to 2.0g / cm3, Rockwell hardness of up to 110. Easy to absorb water, resin gasket strip flatness surface is 10-15um