Koss, a leading manufacturer of high fidelity stereo phones, offers its CS95 single sided headphone with electret, noise cancellation microphone for hands-free communication from your personal computer. It is ideal for telephony, voice activated and voice recognition software and computer games with sound cards with built-in bias supply. It can be used with an external power source if sound card does not have a built-in bias supply. Clear Voice Technology noise cancellation microphone delivers clear communication in noisy environments. Other features include dynamic element for extended frequency response, foam ear cushions for open, hear-through sound, adjustable headband for best fit and straight, single entry 8-foot cord.