The Pentagun is a five-round shotgun manufactured by the Brazilian firm ENARM (Empresa Nacional de Armas).
It has a revolver-type cylinder and could be fired double action only.
Gas blow-by between cylinder and barrel was prevented by means of movable barrel, which was pulled just prior to firing 1.5mm backwards into the corresponding recesses in cylinder.
[2] The shotgun utilizes a straight-line configuration (similar to AR-15) in order to minimize muzzle rise when firing.
This article relating to shotguns is a stub.