Amazon.com: APC AP940-1525A UPS Communications Smart-UPS Signalling Serial RS-232 Cable DB9 to RJ45 (RJ50) - Same as AP940-1525C and AP940-0625A But a Longer Cable : Electronics
Amazon.com: FTDI USB RS232 to DB9 Communication Cable for APC UPS 940 0024C Serial Kable : Electronics