uxcell Knurled Insert Nuts - 50Pcs M4 x 6mm Length x 6.4mm OD Female Thread Brass Threaded Insert Embedment Nut for 3D Printer: Amazon.com: Industrial & Scientific
NUTW-34248 CLS-M3.5-0/1/2 Self Clinching Nuts Clinch Nut Press in Nuts Crimped Rack Server Cabinet Insert Rivet INOX Standard - (Size: CLS-M3.5-1 (1000pcs)/ Type: Standard Nuts) - Amazon.com
Amazon.com: Threaded M4 Insert Kit - 50 Stainless Steel Coil Inserts for Reliable Parts with Frequent Removal | Helical Insert Set for Durable Fastening and Repair : Industrial & Scientific
Amazon.com: M4 Eye Bolt 304 Stainless Steel Heavy Duty Lifting Ring Bolt Screws Pack of 20 : Industrial & Scientific