The Patternmaster Code Black Goose tubes will extend the end of your barrel by 1 1/2 inches and have an effective range of up to 70 meters. The difference between the Patternmaster Code Black Duck and the Patternmaster Code Black Goose is the length of the tube extending from the barrel. (Duck = 1" vs. Goose = 1 ½") The added length is to accommodate a 3 ½" shell while achieving a full pattern. You will see a pattern similar to a "Full" constriction choke on paper, but due to the patented "stud ring" inside the tube, there is a much shorter shot string. This shorter shot string allows for more shot on target at once, so your long-range energy is sure to kill instead of paralyze. All Patternmaster Code Black tubes are made from American manufacturing.