Beretta 1301 Tactical Gen 1/Gen 2 Models, A300 models with a 5 round factory capacity – Complete Package For Beretta models with a 5-round factory magazine tube Features MXT magazine extension designed exclusively for the 1301 Tactical Beretta 1301 extension increases magazine capacity to 7 rounds (capacity determined with 2 3/4″ shells and may vary with shells of differing length) This package has a special +2 extension tube is exclusive to this kit and not available separately. (If you try to build your own kit our standard +2 will extend about 1/2″ past the muzzle) Barrel clamp kit includes 1301 Tactical-exclusive clamp, Picatinny rail, and QDA swivel attachment Utilizes factory magazine spring (spare generic spring included) Weight - 0.52 lbs Dimensions - 6 × 1 × 14 in