Having to repair damaged bolt threads can be aggravating to start with but when the die ends up cross threading the bolt it can lead to lost time and more costly repairs. The Steelman 60381 1/2-20 SAE Split Die Thread Chaser is designed to remove the worry of cross threading by allowing repairs to begin behind damaged threads. By starting the repair on undamaged threads you can ensure a continuous repair that is perfectly aligned with the original threads. Made of hardened high carbon and chromium steel, this tool features dual indexing pins that ensure correct tooth alignment and hold the tool straight and secure during use. With an outer diameter of 1 in., this hex shaped thread repair tool can be used with any 1 in. socket, adjustable wrench, or combination wrench. Designed to meet or exceed 150% of ASME torque requirements, this tool will last for years of reliable use in any professional or home garage/workshop. WARNING: To prevent damage to bolt threads, only use dies with hand-driven tools. Using dies with air, electric, or hydraulic power tools will void warranty.