The Rob Roberts Final Strut Optima HP 20 Gauge choke is engineered for superior performance particularly when using bismuth shot. Its .570 constriction diameter ensures precise shot patterns making it an excellent choice for hunters looking for accuracy and consistency. Crafted from 174 PH U.S. Stainless Steel this choke is part of the renowned RRaptor Series benefiting from years of meticulous product development and cutting-edge technology. Designed exclusively for single-barrel application the Final Strut Optima HP offers unmatched reliability and performance enhancements for your shotgun.