I got this to use my Samsung Convoy clamshell phone with a Scosche &#34;handsfree mic and audio cable.&#34; I plug this 3.5mm to 2.5mm adapter the phone's headset jack, then the Scoche cable into the adapter and the aux input in my car stereo. Now I can use my phone hands free. :) And my callers say the sound quality on their end is good, too.