Flush mount stainless steel tubes available for the many shotguns using the popular Win-Choke thread size and standard Tru-Chokes plus Remington Beretta/Benelli Browning Invector Plus and Mossberg 835 Ultra Mag. These tubes can be used with magnum and steel shot loads. Tru™-Choke Thinwall tubes are recommended for 2¾" Lead Shot loads ONLY. All X-Full and Turkey constrictions are for use with Lead and Hevi-Shot ONLY! View Carlson's Choke Tube Interchange List Mfg: Carlsons SPECS: 1704 Stainless steel heat treated. Available for 12 and 20 gauge depending on model. Win-Choke®-style: .812"-32 tpi (12 ga.) or .687"-32 (20 ga.) fits barrels originally equipped with Win-Choke® Browning Invector Mossberg Accu-Choke® Weatherby IMC® or S