Iver Johnson Choke Tube Features The Iver Johnson improved modified choke tube is machined from stainless steel for long-term durability and resistance to corrosion from weather and powder residue. Built to an improved modified constriction it tightens shot patterns beyond a standard modified choke useful for slightly longer range shots on small game or clay targets. The Mobil choke thread pattern ensures compatibility with shotguns using that specific threading standard. An extended profile extends beyond the muzzle making the choke easier to identify and grip during installation or removal. Stainless steel construction stands up to the heat and fouling generated by repeated firing without degrading performance over time. The improved modified constriction offers a versatile middle ground between modified and full chokes suiting a range of .410 bore hunting and shooting applications. Its extended design also adds a bit of barrel length that some shooters prefer for improved shot stringing. This Iver Johnson .410 improved modified choke tube is for sale at GrabAGun for shooters looking to fine-tune their .410 shotgun s pattern. Iver Johnson Choke Tube Specifications Manufacturer: Iver Johnson Caliber: .410 GA Choke Constriction: Improved Modified Material: Stainless Steel Thread Pattern: Mobil Style: Extended Available At: GrabAGun