tungsten screw 1.quality:ISO 9001, SGS 2.market:USA,Euro,Russia,Japan ... drawing. With excellent machinability, Luoyang Achemetal Co.,Ltd. can forgen tungsten and molybdenum(tzm, mo-la) in bars, rods and blocks ... electrodes, resistance welding electrodes, tubes, crucibles etc. All of our tungsten screw are made of high density and high purtity ...