Brass frame three screw Old Model Ruger Blackhawk .357 Magnum. No transfer bar conversion. This gun has the MR-3DB factory number on the frame as well as the wide trigger. Ruger factory letter confirms that this gun was one of approximately 4290 shipped from the factory in four calibers with brass frames. Previous owner reports that this gun had a $400 trigger job by the legendary Bob James of Phoenix. The trigger is light and breaks smooth as glass. Blue is at 97% with a turn line on the cylinder. Grips with mild handling marks. Overall a very nice and extremely hard to find piece. Ruger letter provided.