The machine pistol Astra Model “F,” 9 mm (0.35") Largo caliber, was created in Spain in the late 1920s, inspired by the Mauser C96. This model was a specific issue for the Civil Guard in October 1934. It was a modified version of the Astra Model 904, with the addition of a mechanism to moderate or slow the rate of fire in machine-gun mode, as it was too unmanageable before that. It also had detachable magazines holding 10 and 20 cartridges. A total of 1,000 of these pistols were issued to the corps. They grew to be one of the most popular weapons, having been assigned mostly to the heads of the lines. They began to be phased out at the start of the 1950s.