StarTech.com 3ft (1m) USB to Serial Cable, DB9 Male RS232 to USB Converter, USB to Serial Adapter, COM Port Adapter with Prolific IC, 1 (Quantity) - Walmart.com
CableMax USB to Dual Serial DB9 5ft.Cable Adapt
Electronic Master USB to RS232 Cable EM620503 - The Home Depot
Mettler Toledo RS232 to USB Converter Cable for XPR Microbalances and Ultra-Microbalances | Fisher Scientific
FTDI Serial TTL RS232 USB Cable | Elektor
Usb To Null Modem (cross Wired) Rs232 Serial Adapter Ftdi Ft232r Usb Rs232 To Db9 Female Adapter Cable Pc Control Tv Cable - Pc Hardware Cables & Adapters - AliExpress