Carlsons Cremator Choke Tube Benelli Crio 2pk 12 ga.Carlsons 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, less flyers and more dense patterns. These benefits make the Cremator Series effective on all types of waterfowl