Rob Roberts Gun Works Raptor Turkey Choke Optima HP 20 Gauge Stainless St. This choke is the ideal option when using TSS or lead. It also works great with any length of barrel. This choke features green Cerakote as well as machined claw marks for extra grip. The Raptor Choke Series uses new technology to deliver a hotter core pattern at distances that are sure to impress. These choke tubes are built from years of product development and innovations using the highest advanced technology available. They are made out of 17-4 PH U.S. Stainless Steel. Specifications for Rob Roberts Gun Works 200265 Raptor Turkey Choke Optima HP 20 Gauge Stainless St: Manufacturer: Rob Roberts Gun Works Fabric/Material: Stainless Steel Gauge: 20 Rob Roberts Gun Works 200265 Raptor Turkey Choke Optima HP 20 Gauge Stainless St