By using electroplating technology, the surface is burr-free and has good heat resistance, high strength and high toughness, as well as corrosion and rust inhibiting properties. ● 【Main use】 A lock washer exerts a spring force between the head of the fastener and the substrate, keeping the washer hard on the substrate and the bolt thread tight on the nut or substrate thread, resulting in more friction and resistance to rotation.
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