... nylon plastic ball, PP polypropylene plastic ball is mainly used in cars, sensor, valves, pumps, valves, bathroom, electronic, bearing, ... / - 0.02 to 0.001 mm, without closing parting line, without burr, smooth surface, high technology, high quality, provide highly ... precise customers choose! Mainly used in cars, plastic ball valves, pumps, sensor, wei yu, electronic ...