JEBS High-Voltage Waterfowl Ported Choke Tube .690 High-Voltage choke tubes engineered to handle steel, lead, bismuth and other shot types with reliable durability and repeatable performance. The patented venturi-style bore profile tightens and concentrates the shot-stream for more consistent patterns and increased on-target energy at extended ranges. Ported construction reduces perceived recoil and helps control muzzle rise for faster follow-up shots while maintaining pattern density. The .690 inch bore is tuned for long to mid-range performance and will perform closer to a long-range choke with larger shot sizes and closer to a mid-range choke with smaller shot sizes. Offered in ported and non-ported models to match recoil and patterning preferences. Pattern testing is recommended to determine optimal shot size and load for the host barrel. Compatible platforms include Benelli SBE II, Benelli SBE III, Benelli M2 and Beretta A391 Xtrema. Durable machining and precise thread engagement minimize fouling and promote long service life for hunting and competitive use.