Abstract: Apparatus for connecting two otherwise coupled railroad vehicles in gaseous flow communication comprises first and second ducts each mounted respectively at one end to one of the railroad vehicles, first and second coupling ducts each mounted respectively at an opposite open end of the first and second ducts to pivot about a vertical axis with one end enclosed in its respective duct and with a second end extending out from its respective duct, first and second frame members each mounted respectively at the second end of the first and second duct and having a mating surface circumferentially surrounding the second end, and first and second biasing means to extend between the respective pair of duct and coupling duct to urge the second end away from its duct and maintain the respective mating surfaces in abutting and sliding engagement one with the other.