... , hand lathe grinder, thread rollingmachine, tapping drilling machine etc3)Advanced measuring & testing equipment: projecting apparatus, roughness tester,hardness tester, concentricity tester etc4 ... Jia Cai Hardware Co.,LtdAdd: TuQiao XiangShan Industrial District, QingXi Town , Dongguan City , Guangdong Province, CHINA. precision stainless or aluminum screw and nut