The Koss CS100 communication headsets boast a full range of sound that helps bring every conversation to life. With high noise sensitivity and reduced sound distortion - not to mention hands-free communication via an electret, noise cancelling microphone - it will seem as if the person on the other end of the line is right in front of you. Whether you employ telephony, voice-activated or voice recognition software - or indulge in computer games with sound cards that feature built-in bias supply* - CS100 headsets offer long-lasting comfort to accommodate the longest of telecommunications. Specifications: Frequency range: 30 - 16,000 Hz, impedance: 32 Ohms, Sensitivity: 91 dB SPL. Cable: Straight, Single Entry, 8ft. Finish: Grey/Black