This Colt Single Action Army Revolver was produced in 1939 and is chambered in .38 Special. It has a 5.5" barrel and is wearing a set of Colt factory rubber grips.
This particular Colt was modified by the King Gun Sight Company. The King Gun Sight company was located on 171-3 Second Street in San Francisco California. They were known for their aftermarket gun sight's and other part enhancements.
The modifications on this Colt SAA include; King Ramp-Red-Bead-Reflector Front Sight ($5 option), King Mico-metered Adjusting Rear Sight ($10 option), King Cockeyed Hammer ($5 option), King Short Action ($10 option). King would charge an extra $20 for Gunsmithing to install all the listed options. The modifications would have totaled $50 over the revolver’s purchase price of $37 at the time it was produced.