Abstract: Apparatus for automatically coupling pneumatic brake lines on railway wagons and other articulated vehicles. The apparatus comprises an axially and resiliently compressible tubular projection which is fitted to the end of the vehicle to extend outwardly beyond the coupling plane of the vehicle. The head at the free end of the projection is formed to align and connect airtightly with a similarly formed head at the free end of a like formation on an adjacent vehicle when the draw-gear of the vehicles is coupled. This action compresses each projection thereby opening a valve between the bore of the projection and the brake line of its associated vehicle. The valve is releasably locked in the open position so that if the vehicles are uncoupled deliberately or accidentally, air in the brake line will be dissipated thus applying the brakes of the vehicle.