Nordic Components makes the best shotgun extension tube on the market. Their MXT modular extension tube and nut system, which are available for most major shotgun manufacturers, makes customizing your tactical, gamer or hunting shot simple and painless. At Arnzen Arms, we have made it easy to get all the necessary components with our Nordic Extension Tube Builder. You can find replacement Beretta A300 Ultima Patrol magazine extensions, Beretta 1301 extension tubes, Benelli magazine extensions, and more! We also carry shotgun magazine extension components including nuts, bolts, and more. Shop our selection below!