Abstract: A base is provided for stationary mounting from a door and includes an elongated upright guide for positioning against the surface of the door which faces in the direction in which the door is moved toward the open position and with the guide located adjacent the lower marginal edge portion of the door near the free swinging edge thereof. A vertically elongated prop member is pivotally mounted at its upper end from an upper portion of the guide for oscillation about a horizontal axis generally paralleling the door surface and for movement between a first inoperative downwardly and outwardly inclined position with the lower end of the prop member spaced above the lower marginal edge of the door and a second operative position with the lower end of the prop member swung toward the door and projecting at least slightly below the door lower marginal edge for engagement with a horizontal surface, such as a floor, over which the lower marginal edge moves when the door is moved toward the open position thereof.