38; 357 CAL (20 GA, 16 GA, or 12 GA)
Shotgun Conversion Adaptor. Allows shotguns to fire either rimfire or centerfire ammunition. Machined from high-tolerance 2011 aluminum with 6-groove rifling. No gunsmithing required. Simply insert the loaded adaptor into the shotgun barrel chamber.
Items ship between 5-10 business days.