Carlson's Choke Tubes are manufactured from corrosion resistant 17-4 PH Stainless Steel. Carlson's Extended Super Steel Choke Tubes are designed specifically for steel shot. They feature a longer parallel section which creates a denser pattern and reduces the occasional flier. The Extended Super Steel Choke Tube extends 3/4" outside the barrel which eliminates damage to the barrel caused by prolonged steel shot use, they feature a knurled extension, blue finish and are backed with a lifetime warranty. Extended Steel Shot Choke Tubes pattern best when using steel shot and typically throw a pattern that is 10-15% more dense than flush mount choke tubes. Your purchase of Carlson Choke Tubes ensures these programs will provide abundant waterfowl and endless opportunities for Duck Hunters through the Delta Waterfowl Organization: Habitat ConservationDelta Waterfowls Working Wetlands Program is now adopted into US Farm BillDuck ProductionPredator Management - The most cost effe...