Hex Head Flange Screw, Class 10.9 (metric)
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Metric flange bolts have a standard hex head with a ‘flange’ beneath which extends out acting as an attached washer to the threaded bolt. This design feature allows the flange bolt to distribute more weight when being tightened, further increasing the strength of the connection without requiring a seperate washer. All available metric flange bolts are non-serrated or smooth on the underside and available in zinc or zinc-yellow for moderate corrosion resistance.