walk through access door for access to duct work & air handling units. Aluminum frame w/ galvanized steel door panel. ” l “handles ship loose with the unit. 1-15/16″ (w) x 1-1/2” deep extruded aluminum frame w/ mitred corners. 3 latches. Mill finish. 26-1/2″w x 50-1/2″h outside flange dimensions. 24 w x 1-5/8″d x 48 h return flange dimensions.