End and Outlet Connections : Integral threads, male or female; and flanges, studded or through-bolted used to join together equipment that contains or controls pressure. (Spec 6A, Spec 16A)
The Mudblogger (Oilfield, Energy and Related Photographs), Oil Field Glossary, TX, USA 2014. http://mudblogger.com/oilfield-glossary/, (Oil - Amer) {777}