Check the listing for details. Patternmaster 12ga Browning Invector DS Duck CODE BLACK - 5487. Color: Gold, Condition: New. Listed at 85.49 USD. Patternmaster's CODE BLACK DUCK tubes will extend out the end of your barrel 1 inch and has an effective range out to 60 yards. You will see a patterns similar to a Full constriction choke on paper with a 2¾" or 3" shell and a Modified with a 3½" shell, 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. Our CODE BLACK DUCK tube can be used with steel or other non-toxic ammunition as well as lead, 2¾" or 3" or 3½" shells. Pick your favorite shot size to use which can range from 8 to T-Shot Non-Toxic/Steel and Lead 8 to 000 Buck. CODE BLACK DUCK tubes only come in a Non-Reflective Bronze titanium coating and are ported. Patternmaster tubes are made of Carpenter Custom 630 (aircraft quality) 17-4ph stainless steel and are heat treated to the optimum level for best performance. Note: Testing done by Ballistics Performance has determined that ammunition with velocity of 1550fps and below will achieve the best results with Patternmaster Tubes. Not for use with ammunition containing flight control wad or slug ammunition. Browning Invector DS chokes fit popular models such as: Browning A5 (2013-Present) Browning 725 Citori