A forty-eight-inch diameter balanced plunger hydraulic valve was one of two originally installed at the base of Buffalo Bill Dam in 1922 to supply water to the Shoshone Powerplant and low-level river outlet works. The two mechanically operated needle valves remained in service until new valves replaced them during the Buffalo Bill Dam modification project of 1985-1993. This valve was manufactured in 1921 by the Wellman-Seaver-Morgan Company of Cleveland, Ohio.