150pcs Stainless Steel Plated Rivetnuts Blind Set Nutserts Threaded Insert Nutsert Cap Flat Head Rivet Nuts M3 M4 M5 M6 M8. 150pcs Blind Rivet Nuts Set M3 M4 M5 M6 M8. F type (flat head), round head knurled (increased torsion strength) design, increase product life.
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