Anvil International offers the broadest line of Malleable Iron Fitting in black finish. Every fitting is manufactured and tested to meet Anvil?s strict quality standards. All Anvil Class 150 Malleable Iron Fittings conform to ASME B16.3 and unions conform to ASME B16.39. All elbows and tees 3/8 inch (10 DN) and larger are 100 percent gas tested at a minimum of 100 PSI (6.9 bar).