When an aluminum rivet is upset against a softer material, a washer must be used under the upset head to prevent eruption of the softer material.

当一个铝铆钉的镦头形成在较软的材料一边时，必需在铆钉镦头下使用垫片以防止较软材料胀裂。

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Precision spring(compression/tension/torsion/special-shape/battery spring), USB stainless clockwork spring, copper, iron and aluminum rivet, nail claw/claw pearl, and toy axle.

精密弹簧（压簧、拉簧、扭簧、异形弹簧及电池弹簧等）、USB不锈钢伸缩发条、铜铁铝铆（窝）钉、爪钉/管珠、玩具车轴。

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