OPIOL QUALITY® Hex Nuts 1.5 D High M6 DIN 6330 Form B Stainless Steel A2 V2A (Pack of 10) Threaded Sleeves Long Nuts Hexagonal Nut : Amazon.de: DIY & Tools
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Threaded Crown Type 3 Size 3 for M6 or 1/4 Inch : Amazon.de: DIY & Tools