1.Cast Iron lug butterfly valve 2. Design standard: MSS SP-67, API609, EN593. 3. Flange to: DIN PN10/16/25, ANSI B16.1 BS4504. cast Iron lug butterfly valve I) Design standard:1:Design standard conform to: MSS SP-67, API609, EN593.2:Connection flange conform to: DIN PN10/16/25, ANSI B16.1, BS4504, ISO PN10/16.3:Top flange conform to: ISO 5211.4:Face to face conform to: API609, ISO5752 series 20, ...