3/8" black coupling. Malleable black iron pipe fittings. Each fitting is individually flag tagged. Import. Mueller logo cast into body of each fitting. 100% inspected and quality tested. All fittings meet the following specifications: Material: ANSI/ASTM A-197 Dimensions: ANSI/ASME B.15.3, B16.14, B16.39. Threads: ANSI B1.20.1. 3/8"