Enhance your listening experience on your Treo. The I4cT combines ultra-premium sound quality via High-Definition driver with Tuned Port Technology added convenience of integrated communication capabilities. The additional utility of the VoicePort(tm) microphone and a multi-function control switch lets you listen to your favorite music and be able to talk on your Treo mobile phone. The 2-function control pod includes a volume control and microphone mute button. The I4cT uses the same technology as Shure's award winning ESeries line of products. The I4cT includes a full selection of sleeves to ensure a perfect fit and a carrying case. Shure makes audio equipment - microphones, earphones, mixers, etc. that are used by professional musicians the world over. Shure knows sound. If your sound is important to you, you want earphones engineered with the same kind of technology that your favorite divas and bands use to be sure they can hear themselves during a performance. That's Shure's "Sound Isolating" technology. Rather than introducing external elements to block out ambient sound (as noise cancelling earphones do), the Shure system creates a sealed environment that keeps noise out, without covering it up by injecting noise-cancelling artifacts that can interfere with your calls or your music. You'll hear details you never heard before.