This lot features a rare philatelic presentation piece containing two complete 50-stamp sheets (panes) of the 4¢ United States Water Conservation postage stamp issued on April 18, 1960. Displayed inside a black and gold display frame, the sheets are meticulously arranged to showcase a complete "Matched Plate Number" set. A custom presentation inscription at the base records that this specific piece was gifted on February 19, 1963, to the Board of Directors of The Metropolitan Water District of Southern California by Director E.T. Ibbetson to commemorate the Seventh National Watershed Congress in Washington, D.C.