stainless steel square plug material: stainless steel 150 LBS size: 1/8''-4'' stainless steel square plugthe thread ends conform to: ASME B1.20.1(NPT), DIN 2999&BS21. ISO 228/1 & ISO 7/1standard: ISO 4144, SP 114, EN-10241, JISmateiral conform to: ASTM A351-CF8M/1.4408, ASTM A351-CF8/1.4401, ASTM A216-WCB, AISI 304.304L,316, 316L,301,430 ETC stainless steel square plug