The Model 1908 Vest Pocket is a compact, hammerless, striker-fired, semi-automatic single-action pistol. Manufactured by the Colt's Manufacturing Company from 1908 to 1948, it was marketed as a small concealable firearm which could be easily tucked into a vest pocket for unobtrusive carry. Designed by John Moses Browning, the Model 1908 followed Browning’s earlier European version, introduced by Fabrique Nationale de Herstal as the FN Model 1906. Both pistols were chambered for the Browning-invented .25 ACP (6.35mm Browning) cartridge.[Known as the Model "N" internally within Colt, the 1908 Vest Pocket is a diminutive 4.5 inches long and has a 2-inch barrel. Weighing a mere 13 ounces, it is fed by a six-round single column magazine.[3] The pistol’s fixed open iron sights were rather small and rudimentary, but typical for small hideout automatics of its era and adequate for the short range at which it was intended to be used. Colt's advertising and marketing literature of the time highly touted the advanced safety features of the Model 1908, including a standard slide-locking safety catch, as well as a grip safety. In 1916 Colt engineer George Tansley invented a third safety feature for the pistol, the magazine safety disconnector, which prevented accidental firing with the magazine removed. This additional safety device was added to production in 1916 or 1917 in the latter 139,000 serial number range, and patented by Colt in 1917. Proud of the state-of-the-art technology represented by this advance, Colt included a green brochure marking its inclusion with every Model 1908 sold for a year after its introduction. Additionally, in approximately the 280,000 serial number range, the left side slide inscription was altered to include the patent date for the disconnector, also known as the “Tansley Device”.[2]