Patternmaster 20ga Ben/Ber Choke Tube Mobile Code Blk Duck CODE BLACK DUCK tubes will extend out the end of your barrel 1 and have an effective range out to 60 yards. You will see patterns similar to a full constriction choke on paper, but because of the patented stud ring inside the tube, there is a much shorter shot string. This shorter shot string will allow more shot on target all at once, so your down range energy is sure to kill instead of cripple. Features: Extends 18" Effective range to 60 yards Same constriction as the classic Long Range Shorter shot string allows more shot on target Tubes have been coated with a bronze titanium blend to better withstand heat and corrosion This tube fits the following guns: Benelli 20ga Nova Pump Beretta 20ga 3901 Beretta 20ga 471 Silver Hawk Beretta 20ga 686 White Onyx Beretta 20ga 687 EELL Diamond Pigeon, Sporting Beretta 20ga 687 Silver Pigeon II, III, and V Beretta 20ga AL391 Teknys Gold, and Gold King Ranch Beretta 20ga AL391 Urika 2 Gold, X-TRA, Youth, Sporting Beretta 20ga Silver Pigeon S King Ranch and IV King Ranch BSA 20ga Charles Daly 20ga Model 106 Charles Daly 20ga S/S Field II Franchi 20ga Franchi 20ga 48AL Franchi 20ga Fenice Franchi 20ga Instinct O/U Mossberg 20ga SA-20 Smith and Wesson 20ga 1000 (Current version starting in 2007, made in Turkey) Stevens 20ga 512 Gold Wing Stoeger 20ga M3020 TR Imports (TRI) 20ga Silver Eagle Traditions 20ga Semi Auto TriStar 20ga Raptor TriStar 20ga Viper Weatherby 20ga PA 459 *This tube is not to be used with slug ammunition, or ammunition that contains a wad/shot cup design as flight control or in flight separation. For best results, Ballistic Performance, LLC, recommends ammunition velocities below 1550fps.