TacStar"s magazine extensions are machined from super-strong chrome moly steel tubing and guaranteed for life. The eight shot extension allows for three extra rounds to the shotgun"s capacity. All extensions include a new spring. Fits: Benelli M1, M2, Super Black Eagle, Super Black EagleII 12 Gauge (DOES NOT FIT THE M3 MODEL) 8 Shot Capacity (varies with Model)