200pcs) DIN 6926 M8 Self-Locking Hexagon Flange Nuts with Serration A4 Stainless Steel, Ships Free in USA by Aspen Fasteners, ASSP692648: Amazon.com: Industrial & Scientific
binifiMux 360pcs M2.5 Black Male Female Nylon Hex Spacer Standoff Screw Nut Assortment Kit: Amazon.com: Industrial & Scientific
Amazon.com: uxcell M5 x 10mm Carbon Steel Rivet Hex Socket Head Insert Nut 10PCS : Industrial & Scientific
ReliaBot 100mm T8 T8x4 Tr8x4 Lead Screw and Brass Nut (Acme Thread, 2mm Pitch, 2 Start, 4mm Lead) for 3D Printer and CNC Machine Z Axis: Amazon.com: Industrial & Scientific