North American Arms

North American Arms is a United States company, headquartered in Provo, Utah, that manufactures pocket pistols and mini-revolvers, also called mouse guns. The company was originally named "Rocky Mountain Arms" when it was founded in 1972. In 1974 it was bought by new owners who renamed the company "North American Manufacturing" (NAM) and then "North American Arms" (NAA).
Mini-revolvers.
The mini-revolvers produced by the company are five-shot, single action revolvers, which have a spur trigger design. They are reminiscent of late 19th century pocket revolvers, the main differences being their size and also that NAA's mini-revolvers are made completely of stainless steel. The design of the mini-revolvers was developed by Freedom Arms, which stopped selling these mini-revolvers in 1990 and then sold the design to North American Arms. Since then, North American Arms has further evolved the design, switching to a safety cylinder design, featuring notches machined halfway between the chambers. As a result, the revolver may be safely carried with all five chambers loaded by resting the hammer in a safety notch. Older NAA mini-revolvers can be retrofitted with this safety cylinder design upgrade at no cost to the owner simply by returning an older design NAA mini-revolver to North American Arms for an upgrade.
The company manufactures revolvers in the following calibers:
The cylinder must be removed from the frame to load or unload all NAA mini-revolvers, with the exception of two models, the "Sidewinder" (swing-out cylinder) and "Ranger II" (break-open cylinder).
Semi-automatics.
In 1997 NAA branched out into semiautomatic concealed carry pistols known as the "Guardian" models to compete with Seecamp. Semi-automatic Guardian pistols are made by North American Arms in the following calibers:
The .25 NAA cartridge was developed by North American Arms based upon a wildcat bottleneck cartridge using .32 ACP brass necked down to grip a .25 caliber bullet, with the goal of increasing penetration beyond what either a .25 ACP or .32 ACP could do. Likewise, the .32 NAA was developed by North American Arms to increase the penetration of a .32 caliber bullet relative to a .380 ACP cartridge.
External links.
 Belt buckle-mini-revolver combination patent