Series 3300 Headsets are designed to provide crisp, clear communications and effective hearing protection in high noise environments. Ground support models, in particular, are designed for interface to standard commercial aircraft interphone systems and Series 3800 de-icing intercoms. The Model H3313 is a dual-ear, over-the-head style headset capable of affording comfort and communication clarity in the most demanding environments. It utilizes the DC-1A amplified dynamic, noise-cancelling microphone housed in a noise-attenuating shield assembly, designed for noise environments above 125dB, intended as a hand-held microphone. The momentary PTT allows microphone transmit only when needed. Durable construction and quality components are found throughout the Series 3300 headsets. Comfort features such as the ear seals and head-pad are specifically chosen for exceptional comfort in any temperature or environmental conditions. Noise-attenuating ear cups provide clear isolated reception and the H3313 provides 26dB of hearing protection. David Clark created the world's first noise attenuating communication headsets and continue to lead the world in delivering quality communication tools.