Christmas Tree 03 : A term applied to the valves and fittings assembled above and starting at the top of the tubing spool on a completed well to control the flow of hydrocarbons and other fluids. (RP 57)
The Mudblogger (Oilfield, Energy and Related Photographs), Oil Field Glossary, TX, USA 2014. http://mudblogger.com/oilfield-glossary/, (Oil - Amer) {777}