ZRM&E 15pcs 1/4 * 25 Zinc Alloy Threaded Insert Nuts with Hex-Flanged Washer for Wood Hex Drive Head Screw-in Type Furniture Embedded Screw Plug: Amazon.com: Industrial & Scientific
Amazon.com: 10Pcs Self Tapping Thread Inserts M8 x 1.25 Female and M10 x 1.5 Male Thread Extension Reduce Sleeve Conversion Kit : Industrial & Scientific
Amazon.com: 4 PCS 34inch Shelving Connectors, Threaded Pole Connectors, Shelving Post Coupler for Extending Wire Rack Shelving, None, Compatible with 34inch Poles : Home & Kitchen