These earbuds by Bose, renowned audio pioneers, have a built-in microphone that allow you to take calls and listen to music on an iPhone, Blackberry, or any other music-enabled cell phone without having to switch earpieces. When you press the answer button on the microphone, an incoming phone call is given signal priority (muting the music), allowing you to converse immediately; another press of the button switches back to your music. They can be used with any portable audio device and provide natural, lifelike sound reproduction and greater low-frequency output, resulting in high-quality audio that has more fullness, range, and clarity than conventional earbuds. The earbuds come with three pairs of different-sized, molded removable silicone tips that allow you to choose one for optimal comfort and fit, unlike common one-size-fits-all earbuds. Includes three cell phone adapters (for use with cell phones equipped with 2.5mm jacks) that supports over 50 cell phone types. Includes protective carrying case and built-in cord adjuster.