This choke tube fits all Beretta 20 gauge shotguns using the "Mobil" choke tube system. It will also fit Benelli 20 gauge shotguns using the "Mobil" choke system. Swarm© "World Record Setting" 20 Gauge Turkey Choke. In 2005 Clark Bush set a new 20 gauge open world record by scoring 32 pellets in 3" at 40 yards. In 2006 Doris Bush set a 20 gauge ladies world record by scoring 30 pellets in 3" at 40 yards. In 2007 Doris Bush won the World Championship in the Women's Hunter Class with a Swarm 20 Gauge Turkey Choke. In addition to that honor she also became the first woman in the history of the event to shoot in the final four in the 20 Gauge Open Class. She defeated all shooters except the eventual winner of that class, with a Swarm 20 Gauge Turkey Choke. This choke tube is rated for all shot types, (no steel) including Hevi-Shot and all tungsten-based shotshells. PLEASE NOTE: I INSPECT AND CLEAN EVERY CHOKE TUBE THAT I SHIP. WHEN YOU RECEIVE IT, IT'S READY TO SHOOT!