M8 - Outer: 16.0mm,Thickness:1.6mm. M8 - Outer: 21.0mm,Thickness:2.0mm. M8 - Outer: 25.0mm,Thickness:2.0mm. M8 - Outer: 30.0mm,Thickness:3.0mm. M4 - Outer: 9mm,Thickness:1.0mm. M8 - Outer: 40.0mm,Thickness:3.0mm.
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