Ideal for routine maintenance, repair work and rethreading where high precision, high tolerance thread is not critical. Straight flutes are ground to provide fast chip removal for efficient threading. Designed for hand threading jobs in a variety of materials. The taps produce a class 2B thread. Tap size and recommended bit size are etched on each tool for easy identification. Thread size: 1/4 inch. Threads per inch: 20. Standard thread: NC. Number of flutes: 4. End shape: 3-5 thread chamfer. Style: Plug Material: high carbon steel.