Tripp Lite 18in USB to Null Modem Serial Adapter FTDI w/ COM Retention M/F 18" - serial adapter - USB - RS-232 - U209-18N-NULL - USB Adapters - CDW.com
Tripp Lite 6ft Null Modem Serial DB9 RS232 Cable Adapter Gold M/F 6' - null modem cable - DB-9 to DB-9 - 6 ft