Zündnadelgewehr
From 1831 to 1839, the Prussians manufactured a caplock conversion of the 1809 Potzdam musket. These were manufactured not only in Potzdam, but also in Danzig. The 1831 musket was replaced with the Dreyse needle gun in 1841, and most of the old muzzleloaders were sold to the Americans for use in their civil war. These were issued to the Union army as late as 1864.