Standard: ANSI B16.5 Class:150, 300, 600, 900, 1500, 2500 Size ... Energy, Nuclear, Automotive, Military, and so on..ANSI B16.5 FlangeClass:- 150, 300, 400, 600, 900, 1500, 2500Size:- 1/2" ... used: - Alloy 20- Nickel 200, 201- Monel 400. K-500- Inconel 600, 601, 625, 718, ... GH3128, GH3030, GH2132, GH1140Our standard Flanges:- ANSI B16.5, B16.47- ASME B16.5, B16.47- JIS B2220- BS10, BS3293, BS4504- ...