Cross ring has excellent acid resistance and heat resistance. It can resist to corrosion of various inorganic acids, organic acids and organic solvents except hydrofluoric acid, and can be used in high or low temperature conditions. Consequently the application range is very wide. Cross ring(packing) can be used in the drying columns, absorbing columns, cooling towers, scrubbing towers and actifier columns in chemical industry, metallurgy industry, coal gas industry, oxygen producing industry, etc