Ideal for routine maintenance, repair work and for re-threading where high accuracy and tolerance thread is not critical. Straight flutes are ground to provide rapid chip removal for efficient threading. Designed for hand threading work in a variety of materials. Taps produce a class 2B thread. Tap size and recommended drill bit size are etched on each tool for easy identification. Thread Size: 1/2in. Threads Per Inch: 20. Thread Standard: NF. No.of Flutes: 4. End Shape: Chamfer - 3 to 5 Threads. Style: Plug. Material: High Carbon Steel.