The Koss iSpark iPhone stereophone was specifically designed for the Apple iPhone. Unique portable earbud stereophone with a specialty ear cushion material which forms slowly in the ear canal providing a custom fit and maximum isolation. Dynamic element for extended frequency response, 10-20,000 Hz. Unique earbud design directs sound into the ear canal for deep bass and extended frequency response. In line microphone and push to talk button. Includes convenient carrying case for protective storage. Also includes one spare pair of large size earcushions. Straight, dual entry 4 foot cord.