These innovative artillery pieces were invented by Robert Parker Parrott in 1860. He was the superintendent the West Point Iron and Cannon Foundry in Cold Spring, New York. These 20-pounders were the largest field guns used in the Civil War and are rarer than the 10-pounders. The Confederates also produced copies of this design. The 20-pounders could fire 19 pound shells a maximum of 4,400 yards. It has "R.P.P." (Robert Parker Parrott) on the right trunnion, "20 PDR" on the left trunnion, "US" on top, "1700 No 221. 1864. W.P.F./D.W.F. 3.67" on the muzzle (1700 pound weight, number 221, manufactured at the West Point Foundy in 1864, and inspected by Daniel Webster Flagle), and an Paulson Bros. Ordnance Corp. carriage.

Fine with black painted finish, mild pitting and oxidation, distinct markings, and mild wear on the carriage.