Our Invector Choke Tubes are manufactured from 17-4 heat treated stainless steel to withstand heavy buffered turkey shotshells. These choke tubes produce extra tight patterns with copper plated and buffered lead turkey shotshells. The Extended Turkey Chokes extend approximately 1" from the end of the barrel and have a matte blue finish. These chokes should not be used with steel shot. These choke tubes are backed by Carlson's Lifetime Warranty and are made in the USA!