Smith & Wesson Model 520, .357 magnum cal. double action revolver.  Serial #N559839, mfg. 1980.  New unfired condition.  Special police contract done of the N-Frame that was never delivered. 3000 run. 4” barrel has mint bore, fixed sights.  Barrel and frame have 100% blue finish.  Cylinder is 100%.  S&W checkered walnut grips are 100%.  Trigger and hammer have 100% case coloring.  The only .357 “N” frame revolver ever made with fixed sights.  Originally ordered for NYS police but never delivered.  S&W blue box is excellent.  Includes instructions.  Rarely seen!