Product Description Increase onboard capacity on your Benelli M4 with the Carlson&&';;s 12 gauge magazine extension. Built from blued solid steel for durability, this threaded extension tube replaces the factory magazine cap to add extra rounds for home defense, competition, and tactical or law-enforcement use. The kit includes an extended spring, a base clamp with swivel stud for use with a quick-detach sling swivel (not included), and installation instructions. Some configurations may use a high-visibility follower depending on the shotgun&&';;s factory setup. Product Highlights Designed to fit the Benelli M4 shotgun (12 gauge) for added capacity Blued steel construction for strength and corrosion resistance 7-shot total capacity when using 2 3/4" shells (includes 1 in the chamber) Threaded tube replaces the factory magazine cap for a clean, secure installation Includes extended spring and base clamp with swivel stud (QD swivel not included) Specs Brand: Carlsons Product Type: Shotgun magazine extension tube Manufacturer Part Number: 04508 UPC: 723189045081 Gauge: 12 Gauge Firearm Fit: Benelli M4 Capacity: 7-shot total capacity with 2 3/4" shells (includes 1 in the chamber) Overall Length: 5 in Material: Steel Finish: Blued Country of Origin: USA Weight: 12 oz Disclaimer: We strive to provide accurate and up-to-date product descriptions, specifications, and images; however, errors or omissions may occasionally occur. We are not responsible for any inaccuracies or discrepancies in the content provided. If you notice anything incorrect or unclear, please contact us so we can correct it. When in doubt, we recommend verifying details directly with the product&&';;s manufacturer.