The Colt Model 1903 Pocket Hammerless is a .32 ACP caliber semi-automatic pistol designed by John Browning. Despite being called "hammerless," the pistol does indeed have a hammer; however, it is concealed under the rear of the slide, making it ideal for concealed carry as it can be easily withdrawn from a pocket without snagging. The pistol operates with a hammer striking a firing pin, driving it into the primer of the cartridge. This concealed hammer design was a marketing feature to emphasize the pistol's suitability for discreet carry. Key features of the Model 1903 include a serrated slide to prevent slippage during manual cycling and dual safety mechanisms: a grip safety and a manual safety. The grip safety, which forms the back strap of the pistol, was a common feature in Colt automatic pistols. Later versions of the Model 1903 also included a magazine safety, preventing the gun from firing if the magazine was removed, even with a round in the chamber. The pistol’s grip panels were made from materials like black checked hard rubber, checked walnut, or special-order materials such as ivory or mother of pearl. Sights were fixed, with the rear sight being drift-adjustable for windage. In 1944, the design was updated with enlarged sights, additional slide serrations, and a switch from a blued finish to a parkerized finish for some models.