Null Modem Cables — Connective Peripherals - Global Store
Amazon.com: StarTech.com USB to Serial RS232 Adapter - DB9 Serial DCE Adapter Cable with FTDI – Null Modem - USB 1.1 / 2.0 – Bus-Powered (ICUSB232FTN) : Electronics
Cable to connect to printer
BB-9PMDS-Serial Splitter, RS-232 MODEM, DB9 M and 2 x DB9 F
Owl POS | Receipt Printers | 6' Serial Port Interface Printer Cable