Universal, AN Fitting, Male AN Weld Bung, AN Size: -12, Flange OD: 1.375", Male AN Weld Bung, AN Size: -12, Flange OD: 1.375", ALUMINUM WELD BUNGS, Weld Bungs, Vibrant Performance male AN bungs are available in both aluminum & mild steel and range from -4 to -20 AN thread sizes., -12ANMaleAlWeldBung.