Rivnuts Stainless Steel Knurled Head Threaded Rivet Nuts, Blind Nutserts M4 M5 M6. M4 Rivnuts. M5 Rivnuts. M6 Rivnuts. - size : M4,M5,M6. M4: Drill Hole Size: 6mm. M6: Drill Hole Size: 8.5mm.
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