Irwin 98912 Metric Tap & Hex Die Set, 41-PieceIdeal for routine maintenance, repair work and for rethreading where high accuracy and tolerance thread is not critical. Taps have straight flutes which 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. Dies are ideal for routine maintenance, repair work and for rethreading where high accuracy and tolerance thread is not critical Taps have