Carlsons choke tube extended turkey 20ga.565 rem choke FEATURES-20 Gauge-Extended choke-Constriction: Turkey-Diameter: .565-Fits Remington-Stainless Steel, blued non-reflective finish-Designed to shoot all lead & Hevi-shot loads-Knurled end-25% longer parallel section to help produce very tight patterns-Not to be used with steel shot Other Features: Desighned to shoot all lead & hevi-shot loads,knurled end, 25% longer parallel section to help produce very tight patterns blued non-reflective finish.