Manufactured in 1917 and overhauled in 1920, with both dates present on the front receiver ring around the "crown/Erfurt" manufacturer's mark. Blade front and tangent rear sights, with a smooth pistol grip stock with "Eagle" over "WaA67" proof on belly and a flat steel buttplate. Trigger guard assembly arsenal renumbered to match receiver. Included with the carbine is a unique blued steel muzzle extension, 6 5/8 inches long and about 11/16th inch in external diameter.