The right counterpart of the thoracic duct, which, as is well known, empties at the level of the left subclavian-jugular angle, at the confluence of the left subclavian vein and the left internal jugular vein. In the majority of people, this vessel has a diameter of less than 5 mm and, often, it is totally absent. However, in a limited number of people, it may be even bigger than the thoracic duct, in which cases it may offset any thoracic duct insufficiency.