A remotely releasable brake hose coupler for pressure fluid operated brake systems, such as on a motor truck and semi-trailer unit, and a retrieval mechanism for retrieving flexible hoses connected to the coupler. Pressure air from the truck tractor brake system is conducted through a valve to an actuator for effecting movement of a coupler member to release engagement with a corresponding coupler fitting mounted on a trailer. One or more air brake hoses connected to respective remotely releasable couplers are connected to tensioning mechanisms and to a movable boom mounted on the truck tractor for extending the hoses during a remote release operation and then retracting the hoses and couplers to a stored position when the remotely releasable couplers are disconnected from the trailer fittings.