Design Features Standard bail and double pin ( male) alloy sub The washpipe and packing are box structure, convenient to replacing on drill floor, no need to disassemble rotary hose and gooseneck, Hole in gooseneck top provides passageway for well logging wireline. Standard gooseneck connection, screw thread conforms to API STD 5B. Conform to API Spec 8A and marked with API monogram.