Amazon.com: RS232 Cable 15ft, DTECH Null Modem DB9 to DB9 Serial Cable Male to Male RS-232 Cord Cross TX RX line for Data Communication (15 Feet, Black) : Electronics
RS-232 Null modem cable
DB9 Null Modem Adapter Male to Male 2 Pack
Shop | 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 - null modem cable - DB-9 to DB-9 - 6.6 ft
StarTech.com USB to Null Modem RS232 DB9 Serial DCE Adapter (ICUSB232FTN)