API6D Check Valve Class 150-1500LBS, NPS 2-36" Basic Design: API 6D Face to Face Dimension: ANSI B16.10 Flanged Ends: 2-24" to ANSI B 16.5, >24" to MSS SP-44, to API 605 on request B.W. Ends to ANSI B 16.25 Manufacturing to NACE MR-01-75 on request We designed this specialtype of check valves in full bore. Also we can design them according the clients' requirements.