Type: M3 M4 M5. Height:4mm(M3) 8mm(M4) 10mm(M5) (Optional). Size：approx M3×Φ4.5×H4mm /M4×Φ6×H8mm/ M5×Φ7×H10mm. These bolt nut washers are perfect for outdoor household and industrial applications. The material is made of high-quality copper, which has high corrosion resistance, high toughness and wear resistance.
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