L-COM Slimline Null Modem Adapter, DB9 Male / Female DMA060MF
Amazon.com: DTECH DB9 RS232 Serial Cable Male to Male Null Modem Cord Full Handshaking 7 Wire Crossover for Data Communication (1.5 Feet, Black) : Electronics
Serial Port 9 Pin Null Modem Adapter DB9 Male / Male RS232
Null Modem Adapter Serial DB25 Male to Male | Computer Cable Store
L-COM Deluxe Null Modem Cable, DB25 Male / DB9 Female, 25.0 ft CSNULL259MF-25