Strong, lightweight aluminum clamp attaches securely to barrel to provide extra support for extended magazine tube. Eliminates unwanted vibration under recoil to ensure smooth, reliable feeding of rounds. Low-profile design, rounded edges, and flush-mounted hex-head machine screws prevent snags and damage to patrol car interiors; hardcoat anodized surface adds strength and exceptional resistance to surface abrasion. Available in Standard model and Tactical Rail configuration with Picatinny-type accessory rail that may be positioned on left or right side of clamp for mounting flashlights and other accessories. Also available for heavy barreled shotguns/Mossberg. Mfg: Nordic Components SPECS: Aluminum, hardcoat anodized, black, matte finish. Fits shotguns equipped with Nordic and DPMS extension tubes. 12 gauge only. Standard - 2 oz. (57g) weight. Rail - 2.6 oz. (73g) weight. Mossberg - Fits Mossberg shotguns, including the 590 and 930SPX.