A roller blind tube with fabric wound around it is mounted in brackets that have spade-shaped elements (3) provided in the axis. These elements cooperate with oblong holes (2) in terminating plugs (1) in the roller blind tube. According to the invention the oblong holes (2) are opened by rotating excentrically built rings (8). Hereby the roller blind may be hung on the brackets, whereupon the rings (8) are closed again.