Browning Diana Grade choke tubes produce tighter patterns than Browning Invector Plus choke tubes. Features: - Stainless steel barstock and heat treated prior to machining - Titanium nitride surface 72RC harness for excellent wear and reduced plastic build-up - Absolutely perfect concentricity to provide superior patterning Specifications: - Choke: Cylinder - Color: Titanium Nitride, black band - Gauge: 12 Gauge - Type: Invector-Plus