"QD" stands for Quick Disconnect.
The Plantronics QD (quick disconnect) is a proprietary connector featured on the “H” and “P” series headsets. It connects the headset to the matching cable providing in a simple user friendly but reliable connection. It allows the user to disconnect the headset if needed during a call and reconnect; this is similar to placing the call on hold.
This is a feature that allows you to walk away from the telephone without having to remove the headset.
old version (used before 2005)
new version (2005-2008)
newest versions (2008 and beyond)
The headsets are sold separately from the amplifiers so you can choose the style that fits your needs.
The H series headsets work with amplifier models M10/M12, A20, CA10, MX10, E10, P10 & SQD.
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