1.bearings balls for high temp, low temp,electric insulation,measure pumps 2.valve balls for acid,alkali, salt, measure pumps 1.Usage: bearing balls for canner pump, magnetic drive pump. Vacuum pump, fixed anode X-ray tube shaft; bushing bearing for strong acid, strong alkali, salt, measure pumps, flow meter and deep well pump; bushing bearings for nonmagnetic to hydrofluoric acid.2. ...