Abstract: A device for transfer of preferably fresh air from a stationary place to a movable place. A stationary elongated box with fresh air supply is provided with a longitudinal slot closeable by a tightening band bearing against the rigid inside surfaces of the box at each side of the slot. A connection body projects through and is movable along said slot and is provided with guide edges against the inside surfaces of the box adjacent the slot and with backing rollers bearing against the outside parts of the box along the edges of the slot. Further, the connection body has a slide part locating inside of the box for lifting the tightening band from the slot edges and has passages permitting air to flow from the box through the connection body and to an outlet pipe connected to the movable place.