The Rob Roberts Final Strut Invector Plus 12 Gauge choke is an expertly crafted accessory designed to enhance your shooting experience. Built from 174 PH U.S. stainless steel this choke offers exceptional durability and performance. Its .660 constriction diameter is specifically engineered to optimize the use of bismuth shot shells making it a valuable addition to your shotgun. Part of the esteemed RRaptor Series it embodies years of meticulous product development and innovative technology ensuring superior results. Note that this choke is designed for single-barrel placement providing targeted precision and reliability.