Carlson's Choke Tubes are available for most shotgun models and serve as a perfect replacement to damaged worn out or misplaced factory choke tubes. Carlson's Choke Tubes are manufactured from corrosion resistant 17-4 PH Stainless Steel they are compatible with steel or lead shot (Steel shot should not be used in any Turkey Choke Tube) and are backed with a lifetime warranty. - Technical Information: - Gauge: 20 - Thread Pattern: Remington Rem Choke - Popular Firearm Models: Remington 870 1100 and 11-87 - Ported: No - Shot Type: Hevi-Shot lead or copper plated lead - Constriction: Turkey .575 constriction - Material: Stainless Steel