They are appropriate for threading a wide variety of materials both ferrous and non-ferrous. The nominal size of a Pipe Tap is that of the pipe fitting to be tapped, not the actual size of the tap. Size: 2-11-1/2 NPT, Material: Carbon Steel, Finish: Uncoated (Bright), Style: NPT, Cutting Direction: Right Hand, Tap Size: 2 NPT11-1/2.
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