FLANGE NUT ZINC METRIC

Yellow zinc metric flange nuts are available in various sizes and types, primarily made of high-tensile carbon steel with a yellow passivate finish for moderate corrosion resistance. They are widely used in the automotive and general engineering industries because the integrated flange acts as a washer, distributing load and often featuring serrations for a locking effect. 

Product Information
Material: Most are made from high-tensile carbon steel, graded as Class 8.
Finish: The zinc yellow passivate finish provides better corrosion protection than standard clear zinc plating and is common in automotive applications. This coating is generally intended for internal use as it offers an average level of external protection.
Design: The key feature is the wide, non-spinning flange under the hex head, which acts as a built-in washer to distribute the clamping pressure over a larger area. This design saves time during installation and is useful for oversized or irregular shaped holes.
Types: Serrated types provide a locking mechanism to prevent loosening under vibration by angling into the mating surface, making them unsuitable for use with a separate washer or on surfaces that can be scratched.
Thread: Available in both coarse and fine metric thread pitches (e.g., M8-1.25 coarse, M10-1.25 fine) to suit various applications.