Tap and Die Set: 1/4-20 UNC thread tap and round die. 20mm die stock fits 11mm-20mm / M3-M4 capacity, with adjustable screws. Suitable for making or repairing male and female threads. Good for general purpose applications.Application: Can re-thread existing threads in hard materials like metal, or make new threads in soft material like plastic. Used to process mild steel, aluminum, stainless steel, iron, cast iron, alloy steel, and hard plastics, etc.Special Design: High-speed steel machine tap is with high hardness and toughness for wear resistance. Features just the base substrate without any additional coatings.
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