Color: 2PackDB9 Female To DC 3.5 mm Cable 6feet DB9 Female to 3.5 mm Serial Cable DB9Pin Serial Transfer Cable For Devices Stereo 3.5 mm Jack to DB9 Pin Female Serial Port. Primarily used to transfer Serial Data back and forth from Small devices.
Wiring Schematic: DB9 TRS Connector / Audio DC 3.5 mm Pin 1-6-7-8 open Pin 2 Tip - Left Pin 3 Ring - Right Pin 4 open Pin 5 Shield - Ground Pin 9 open