Knurled - Serrated - Steel Large Head Rivnuts Rivet Nuts Nutserts Blind M3-M12. Open Style, Zincplated Steel Cylindrical Grooved Large Head Rivnuts. M8 16.5mm 0.5mm-3mm 16mm 1.5mm 10.9mm. M8 XL 18.5mm 3mm-5.5mm 16mm 1.5mm 10.9mm.
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