Union nut Specification: DN10-DN150, 1/2"-6", larger size can be customized Materials: AISI304, ... (ISO9001: 2008, CE, TUV certified) Specification: DN10-DN150, 1/2"-6", larger size can be customized Materials: AISI304, AISI304L, ... polished Ra less than 0.4 - 0.8μm, outer surface glass polished Ra less than 0.8 ... μm. Standard: DIN, SMS, ISO, IDF, RJT, AS, BS, ...