Amazon.com: StarTech.com 2m Black DB9 RS232 Serial Null Modem Cable F/F - DB9 Female to Female - 9 pin RS232 Null Modem Cable - 2 meter, Black (SCNM9FF2MBK) : Electronics
Null Modem RJ45-DB9 (Female) Adapter for C2-RJ45 Console Cable - Get Console Shop
Amazon.com: DTech DB9 RS232 Serial Cable Male to Female Null Modem Cord Full Handshaking 7 Wire Crossover for Data Communication (1.5 Feet, Black) : Electronics
USB To Null Modem FTDI Serial Adapter, 18-in. | Eaton
Null modem cable
Null modem cable
File:Null modem cable 1.jpg - Wikimedia Commons
Null modem - Wikipedia
What is null modem? Null Modem cable vs Straight serial cable
Crossover or "Null Modem" vs. Straight Through Serial Cable - Decisive Tactics, Inc.
6ft (1.8m) DB9 F/F Serial RS232 Null Modem Cable - Black | Serial RS232 | Computer Cables | USB and PC