Machined steel magazine extensions enhance capacity without requiring gunsmithing or permanent modifications to your Remington 870, 1100 or 11-87 shotgun. The knurled, threaded collar attaches securely to the end of the magazine tube. This product includes a high-performance, extended length magazine spring and a durable, high-visibility nylon follower. The loop model is equipped with a fixed loop on the underside of the extension, allowing for the direct attachment of tactical-style slings without the need for swivels. Compatible with 12 Gauge shotguns only.