VEVOR Thread Chaser Set: Your Reliable Repair Assistant.This thread chaser set is expertly crafted from high-quality steel with a hardness rating of HRC55-62, ensuring corrosion resistance and long-lasting durability. The 61-piece set includes various dies, taps, and thread files designed to efficiently restore worn threads and remove rust. It is suitable for a wide range of screws and automotive parts, such as cylinder heads. With multiple tool specifications covering UNF, UNC, and metric sizes, the set is color-coded for quick identification.