Coarse-Thread Series: This series, UNC/UNRC, is the one most commonly used in the
bulk production of bolts, screws, nuts and other general engineering applications. It is also
used for threading into lower tensile strength materials such as cast iron, mild steel and
softer materials (bronze, brass, aluminum, magnesium and plastics) to obtain the optimum
resistance to stripping of the internal thread. It is applicable for rapid assembly or disassembly,
or if corrosion or slight damage is possible.