This rudder bar was used on a British Airco Dh. de Havilland aircraft which flew during the war; it is not clear which type but it was most likely the DH.2, DH.4 or DH.9.  It measures 27-3/4 in. or 70 cm in length.  The inked and numbered A.I.D. inspector's stamp on the wood (upside down in the photo) stands for Aeronautical Inspection Directorate and, based on this, we know that this rudder was used in a British-made aircraft, not one of the American-made aircraft which were based on the British design. The metal is additionally stamped with "A114" within a triangle, though it could also be "AH4."  The previous owner stated that their ancestor was a veteran who removed this rudder from an aircraft that crashed during the war.  While the rudder bar, itself, is completely original, the vertical steel rod around which the rudder bar pivots and the wood base below it were made by me in my shop from original drawings of the American version of the British Dh.4 made by the Dayton-Wright Co and kindly loaned to me by Dorian Walker.  The last two photos show the rudder bar in the cockpit of the original DH.9 at the Australian War Memorial.