StarTech.com DB9 to RJ45 Modular Serial Adapter - Black - GC98FF - Cable Connectors - CDW.com
readstar]100pcs/lot Rj45 Coupler Network Cable Connector Female To Female Cable Extension Adapter Network Through Head - Computer Cables & Connectors - AliExpress
1-Port USB 1.1 Over Cat5 Superbooster™ Extender Dongle RJ45 Female to USB B Male Receiver | USB Extension Cables and Devices | USB Cables, Adapters, and Hubs | USB and PC
Revo RJ45 Female to Female Indoor Network Coupler (4-Pack) NC-1BNDL4 - The Home Depot
RJ Lnxx Industrial RJ45 Bulkhead Passthrough Connector from Molex Part Number ENSP1F5