U.S. Model 1917 green wool tunic issued to a machine gunner attached to the Siberian American Expeditionary Force. The jacket bears the rare black, diamond-shaped 'S AEF' shoulder patch applied to the left shoulder, and a Victory Medal ribbon applied to the left breast. Screw-back brass collar discs include a 'US' disc and a '27 M.G.' disc. The owner's serial number and name have been inked inside the collar: '477811 SERCOTT A.E.F. SIBERIA' The tunic is in excellent condition, with all buttons present, no rips or tears, and only two or three very isolated and very small moth holes, one slightly oxidized button. Very rare.