Maximum Range Turkey Choke Tube. Designed to increase the range and pattern density of your favorite turkey gun! The Jelly Head Maximum utilizes an extended taper and fluted ports to tighten patterns up to 20% and reduce recoil allowing you to stop Gobblers in their tracks at even longer ranges! We utilize proprietary Black-T coating, the same protective barrier utilized by the militarys Special Forces to prevent rust and corrosion on weapons in the harshest environments, like turkey hunting.Instructions:1. Clean the threads in the muzzle and on the JellyHead Choke Tube before installing. Use a good choke tube grease to coat the threads before installing.2. Screw the tube into the muzzle, be careful to not cross-thread. Grip the knurled end and hand-tighten only. No tools needed. DO NOT OVER TIGHTEN.3. Periodically check tightness of the tube.4. Not to be used with Steel Shot.Warning:JellyHead Choke Tubes are not designed to shoot steel shot. Check and make sure your gun is unloaded before installing or removing the JellyHead Choke Tube. Make sure barrel is clear and never fire a shell when barrel is obstructed, serious injury and barrel damage could occur..655 Constriction (12 GA Beretta/Benelli Mobil)