Carlson's cremator choke tubes feature triple shot technology (tst) and is offered in close, mid, and long-range constrictions.Tst is a series of three graduated rings in the taper section of the choke tube that allows a more gradual transition from the shotgun bore to the final constriction.This design offers reduced pellet deformation, fewer flyers, and more dense patterns.These benefits make the cremator series extremely effective on all types of waterfowl throughout the entire season.The cremator series has no size or speed restrictions with steel shot in any of the three constrictions.You also get all the benefits of an extended choke tube, including a 25% longer parallel section for tighter and denser patterns, wrench-less installation, quick removal and helps with muzzle protection.Made in the usa.Approved: Steel,Lead,Non-ToxType: Choke TubeGauge: 12 GaugeConstriction Type: Mid-RangeConfiguration: Benelli Crio PlusFinish: BlackConstrictiondiameter: .707 Mid RangeChokes Included: 1Material: 17-4 Stainless SteelPorted: No