This vintage Imperial German Army button, featuring the Prussian crown symbol, was issued during the era of World War I (1914-1918). The button, measuring 20mm in size, is a collectable piece representing the military service of Germany during this historical conflict. With a strong connection to the Prussian army and the German Empire, this button is a valuable piece of militaria history that offers a glimpse into the uniforms and insignia worn by soldiers during the First World War.