StarTech.com 3ft (1m) DB9 to 3.5mm Serial Cable for Serial Device Configuration, RS232 DB9 Male to 3.5mm for Calibrating via Audio Jack - First End: 1 x Mini-phone Stereo Audio - Male - Second End: 1 x 9-pin DB-9 RS-232 Serial - Male - Shielding - Nic 9M3