Vehicle door with a fixation element for a sealing at the end of the door

The fixing unit has a fixing surface (20), which is parallel with another surface of a door of a vehicle. The surface (20) is paired with the latter surface. A corner part (22) interdependent of the surface (20) has a surface (32) which carries a joint. The surface (20) has an opening on the door, and the corner part (22) to present the fixing unit on the door.