Revolvers are sidearms that can be used by all classes.
Revolvers are defined by their use of a revolving cylinder (hence 'revolver') that holds ammunition instead of a magazine as used in most automatic pistols. In popular media revolvers are often represented as powerful "hand cannons", often chambered for a magnum pistol cartridge - a popular example is the Dirty Harry film series. However, in reality revolvers vary in power, just as automatic pistols do.
Currently, the only revolver is the MP412 REX.