With 17 taps and 17 dies in a full range of coarse and fine sizes from #4 to 1/2 in., the TEKTON 39-pc. Tap and Die Set (Inch) is the ideal all-purpose set for your garage or shop. These tapered plug taps and dies are the most commonly used style and are perfect for most hand threading applications. They are known for their ability to start easily, either cutting new material or chasing lightly damaged threads. With proper technique and the right lubricant, these taps and dies will cut mild carbon and alloy steel, cast iron, aluminum, brass and bronze.