Door for Duct Access with no hinge has an insulated door panel, along with the gasketing between the door and frame assures a tight seal without obstruction in the air system. Unit comes with extra – self tightening, hand operated cam latch(es) making the door panel completely removable. Galvanized steel material with mill finish. 4 Latches. Silver Finish. 20″W x 20″H Outside Flange Dimensions. 18-3/4″W x 18-3/4″D x 5/8″H Return Flange Dimensions.