Iver Johnson Choke Tube Features The Iver Johnson Choke Tube is built from stainless steel a material selected for its resistance to corrosion and its ability to withstand repeated cleaning and exposure to shotshell residue. Its improved modified constriction produces a tighter shot pattern than more open chokes making it a solid choice for hunters and clays shooters working at moderate to longer distances. The extended body design makes the choke easy to grip for hand installation or removal cutting down on the need for a dedicated choke wrench during routine changes. Built on the widely used Mobil thread pattern this choke fits a broad range of 20 gauge shotguns designed around that standard. Shooters who want a dedicated choke for pass-shooting or longer range clay presentations will find the improved modified constriction a useful addition to their choke lineup. Stainless steel construction also helps this choke resist the pitting that can develop over time in tubes exposed to solvents and high humidity storage. Because it follows the Mobil thread standard hunters can swap this choke into their 20 gauge shotgun quickly before heading afield. The Iver Johnson 20 Gauge Improved Modified Choke Tube is available now at GrabAGun for shooters who need a reliable option for moderate to long range shooting. Iver Johnson Choke Tube Specifications Manufacturer: Iver Johnson Type: Choke Tube Choke: Improved Modified Flush or Extended: Extended Gauge: 20 GA Material: Stainless Steel Thread Pattern: Mobil Available At: GrabAGun