1.Efficient Thread Repair: Skip costly replacements! This thread repair kit quickly restores worn or damaged threads without damaging the metal. Perfect for fixing rusted fasteners, bolt holes, and engine components. 2.49Piece Comprehensive Kit: Includes essential taps and dies: UNC (Silver): 9/16'12, 1/2'13, 7/16'14, 3/8'16, 5/16'18, 1/4'20, plus 5/8'11 die. UNF (Black): 9/16'18, 1/2'20, 7/16'20, 3/8'24, 5/16'24, 1/4'28, plus 5/8'18 die. Metric (Gold): M14x1.5, M12x1.75, M12x1.5, M12x1.25, M11x1.5, M10x1.5, M10x1.25, M10x1.0, M8x1.25, M6x1.0. 3 Thread Files: SAE and Metric sizes. 3. CorrosionResistant Crafted from heattreated steel with a galvanized coating and black phosphate treatment, this set excellent corrosion resistance and durability, with a hardness of HRC 55. The hex design ensures compatibility with any wrench or socket for rethreading. 4.Compact Organized Comes in a sturdy blowmolded case for easy storage and transport. Colorcoded tools for identification of UNC, UNF, and Metric standards.