Iver Johnson Arms Iver Johnson Choke Tube 20ga. Improved Modified Mobil Choke

Iver Johnson Arms Iver Johnson Choke Tube 20ga. Improved Modified Mobil Choke. The Improved Modified Steel Choke Tube is generally considered to be the most successful and versatile choke tube to ever hit the shotgun market. The design has been tried and tested many times with great results. This particular choke tube has been subjected to torture tests which have proven it to be more durable than many other steel choke tubes. It has also been the subject of much research by Iver Johnson Arms. U