The heat shield clamp washer is made of high-strength 65 manganese steel, which is impact and wear-resistant, harder and tougher, durable, and high-temperature resistant. The lock washer exerts an elastic force between the fastener head and the base body, so the washer barely touches the base body, while the screw thread rests tightly against the nut or base body thread, creating greater friction and rotational resistance.
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