Iver Johnson Modified Mobil Choke Tube Features The Iver Johnson Modified Mobil Choke Tube is machined from stainless steel giving it strong resistance to corrosion and wear even after repeated cleaning and extended use in the field. Its modified constriction tightens shot pattern more than a cylinder or improved cylinder choke making it a solid choice for mid-range shots on upland birds and small game with a .410 bore shotgun. The threads are cut to the Mobil choke pattern so it installs directly into shotguns built around that threading standard without any additional fitting. Choosing the correct constriction for the intended target and distance is one of the simplest ways to improve pattern performance and this modified option covers a versatile middle ground. Built with an extended profile the choke tube sits proud of the muzzle for easy visual identification and simple hand installation or removal which speeds up changes between hunting situations. This extended design also makes it easier to keep track of which choke is currently installed when switching tubes in the field. As a stainless steel component it is well suited to the damp muddy conditions often found during waterfowl and upland hunts without concern for rust. The Iver Johnson Modified Mobil Choke Tube is a practical durable upgrade for any .410 shotgun owner shooting for sale at GrabAGun. Iver Johnson Modified Mobil Choke Tube Specifications Manufacturer: Iver Johnson Model: Modified Mobil Choke Tube Gauge: .410 GA Choke: Modified Style: Extended Material: Stainless Steel Thread Pattern: Mobil Available At: GrabAGun