Colt 1903 Serial Number 13960 is considered a type 3 variant of the model M. It was shipped to the Salt Lake Hardware Company in Salt Lake City, UT on May 14th, 1913 in a 10 gun shipment. It features Colt's high polish blue finish with fire blue small parts. Note the type 2 rubber grips and the lack of the thumb safety retaining screw.
The rampant colt on the rear of the slide has also changed from being encased in a circle to now standing on his own.