Ultimate Arms Gear 1-3/16"X16 RH Right Hand Threading Gunsmithing Receiver, Adjustable High-Speed Steel Round Die 1-3/16"X16 RH Right Hand Round Die is Chamfered on Both Faces. Adjustment is Obtained by a Fine Pitch Screw which Forces the Sides of the Die Apart, or Allows Them to Spring Together. Use to Make Custom or Clean Up Existing Factory Threads. Custom-Made to Factory Specs. Great for Receiver, Lower. Made of High-Speed Steel. UN Unifed Fine