Get high-quality Carbon Steel ASTM A105 Welding Neck Flanges from ASME B16.5 standards provider. These flanges are 4 inches in size, with a 100 mm diameter, rated at Class 300 LB, and designed for SCH 80 piping systems. Featuring a Raised Face and Serrated Spiral Finish, they adhere to ISO 10474-3.1B standards.