1.we are the pioneer of ceramic bearing in China 2.material is SSiC 3.full ceramic bearing 4.we ... ,vacuum,fixed anode X-ray tube,high temp,low temp,electric insulation,high precision ballscrew set,valve balls for acid,alkali ... .Characterisitic:resistance to strong acid,strong alkali,salt and gas of deleterious, especially resistance to hydrofluoric acid,long life,high hardness ...