WEB3-Piece Full Port Low Temperature Carbon Steel Class 600 NPT Ball Valve. Standard Compliance - Valve design: ASME B16.34, Class 600, End Connections: NPT per ASME B1.20.1, Valve Marking: ASME B16.34, Production Testing: ASME B16.34, NACE MR0175, 2000 edition. FEATURES.