1. Dies are used to cut or clean an external thread. 2. Dies are best used with a three screw die stock which aids in the alignment when repairing threads. 3. Round Adjustable Dies are made with a slot in the circumference and a special screw to allow for cutting a slightly smaller size. 4. Hex rethreading dies are used in repair of rusty and/or damaged threads. 5. The chips are discharged through the plane holes inround dies. 6. They are either used for manual use of die holders or clamped into the quill to use in a turning lathe.