Nws qhov zoo yog siab dawb, purity thiab pob tshab, super tsis tshua muaj hlau cov ntsiab lus, tsis muaj hnyav hlau thaum tshav kub kub-resistant, acid-resistant alkali-resistant, thiab kuj nws resistant rau corrosion ntawm noxious gas, ruaj khov kev kawm thiab zoo rwb thaiv tsev.