Abstract: A spindle which is rotatably mounted in a box-like housing rotatably carries a tube. A spring is connected between the tube and spindle to exert a biasing rolling force on the tube. A stop member holds the spindle fixed with respect to the housing to permit rolling of the tube. An upper edge of a mesh screen is fixed to the tube so that the screen can be rolled up on the tube. Lateral channel shaped guide members extend downwardly from the housing and guide edges of the screen. A fastening member is connected to a lower edge of the screen and includes moveably mounted pins which are engageable into recesses in the guide members to hold the fastening member down and cover an area with the screen. The housing can be mounted over a window or door so that the screen can be pulled down over the opening of the window or door.