Even though the M Models are Single Action pistols, they are improved designs of the "old" (but still efficient) "Rosarina" model. Newest models, like the M02 AR and M03 AR have new Fast Action (Acción Rápida in Spanish) designed by the Fabrique Nationale, which allows them to be fired like a Double Action, but still being a Single Action. Although the M Models are improved Designs of the standard High Power, they are made by license of FN, because the actual design is the same as the Mark II Pistol.