This Ruger manufactured blue finished steel grip frame with the squared back trigger guard is for the old model Super Blackhawk single action revolver and is in very good condition with light wear. This grip frame may have a plumb brown finish rather than the darker blue finish which was not uncommon on these older 3 screw grip frames.  (file photos)

Note: Ruger old model Super Blackhawk single action revolvers with the following serial numbers have been observed with this part: 7078, 9425 & 24120.