My Thunder 45 is a full size short recoil semi-automatic pistol manufactured by Bersa at the Ramos Mejia production plant in Argentina. The slide and barrel are high strength steel and the frame is aluminum alloy. Available finishes are black matte, nickel, and a two-tone with a nickel finished slide and satin black frame. All the available finishing styles are non-reflective. The trigger is double-action for the first shot, single-action thereafter. The magazine is double stack and the slide remains open after the last round is fired. The magazine release button can be reversed for left-handed shooters and it has a "round in the chamber" indicator.