Earhook converts from over-the-head to over-the-ear use. All models available with voice tube or noise-canceling microphone. Reduces background noise and incoming loud tones while enhancing call clarity. Compact, lightweight headset with superior acoustics and sound reception. Quick Disconnect? lets you leave your desk while the caller remains on the line. Adjustable clothing clip. For either ear. Amplifier (sold separately) is required for operation.