Carlson's presents their solution to upgrading the capacity to you favorite shotgun. Made from blued solid steel, Carlson's Shotgun Magazine Extensions include everything you need to install: spring, base clamp, and a high visibility follower. Simply by replacing your magazine tube cap and spring, you can add rounds to your shotgun's capacity with ease. The Carlson's Shotgun Magazine Extension is an ideal accessory for home protection, self defense and competition shooting.