It has a simple blowback operation, with a single- and double-action trigger mechanism, and exposed hammer.

[2] The Beretta 21a chambered in .22 LR or .25 ACP is a pistol that’s intended for undercover agents, as backup for police officers, for individuals licensed to carry a concealed firearm or just for plinking and/or sport shooting.

The barrel pivots on a pin under the muzzle so that the chamber may be loaded with the slide in the closed position.

[5] The Bobcat was designed without an extractor, relying on pressure from the expanding gases of the fired cartridge to simply blow spent cases from the chamber.

[2] In the .22 LR "Inox" version (introduced in 2000[1]) only the barrel and slide are stainless steel, and the alloy frame has a matte light gray Bruniton coating.