Black Long Dock Extension Extender Cable 30-pin Male to Female 100 cm = 1 Meter = 3.25ft = 39.37 inches for iPod and iPhone 4 iPad 2 - Audio Extension for Bose Sony iHome & other Docking Stations - Extend Your Car Audio Dock
THIS DOES NOT WORK WITH IPHONE 3GS IF YOU HAVE AN OTTERBOX DEFENDER CASE.  One of the main reasons I got this was because I needed an extension for an audio cable in the car.  I have an Otterbox Defender case for my iPhone 3gs, and as all you who have these case know, sometimes it's a pain to get accessories that will work with them.  This one is no different.  After some modifications with a Dremel, I can use it as intended.  But don't think that it will work straight out of the package if you have an Otte