Confirmed by the Colt factory letter this pistol was an experimental prototype kept by the Colt factory. The letter also confirms the caliber, barrel length, finish and type of stocks. Pistol has fixed sights, standard model marking on left side of slide, two-line caliber marking on right side of slide, and two-line Hartford address over the serial number on the right side of the frame. Magazine absent. Consecutively numbered to the previous lot.