The Gold Standard for choke tubes. What makes it different? First . . . the longer choke taper inside Diana Grade choke tubes improves pattern performance. These tubes offer a superior construction from stainless steel bar stock that is heat treated prior to machining. The use of a titanium nitride surface with 72HRC hardness provides excellent wear and reduced plastic buildup. And they look very very good on the muzzle end of your Browning Citori. – Stainless steel barstock is heat treated prior to machining – Titanium nitride surface 72HRC hardness for excellent wear and reduced plastic buildup – Absolutely perfect concentricity for superior patterning – Extends beyond the barrel for easy removal and installation – Material: 17-4 Stainless Steel – Color: Titanium Nitride – Pockets: Titanium Nitride – Choke: Gauge 28 – Choke Pattern Percentage: 45%-75% – Length: 0.025 – Weight: 4.8 oz