If your Treo smartphone pulls double duty as a phone and an MP3 player, then the 2-in-1 Stereo Headset Pro is perfect for you! This fully functional smartphone headset is specially designed to deliver amazing sound quality for digital audio content. Enjoy your favorite tunes with rich, dynamic stereo sound through the high-performance earpieces. Got an incoming call? Switch instantly to call mode with the touch of a button right on the microphone.