the double door security device uses at least two opposed hinges of the double door pair to secure corresponding door bar retainers to the door frame structure . the hinge pin is removed and the door bar retainer is placed upon the hinge , with a hinge pin of suitable length reinstalled through the hinge to secure the door bar retainer pivotally to the hinge . the door bar retainer , in combination with the hinge , defines a door bar passage for the removable installation of a door bar therethrough . the retainers may be configured to accept door bars having various cross sectional shapes , e . g . two by four lumber , square and round tubing and pipe , etc . the hinge attachment ends of the retainers are preferably beveled to minimize marring of the door and door frame adjacent to the hinge , and to serve as a door stop limiting the opening swing of the door .