Plantronics SupraPlus H251N, H261N, HW251N. HW261N & Avaya AW450N, AW460N. (a.k.a. SupraPlus Microphone Arm). It is for Plantronics SupraPlus series headsets. This item is unused and compatible with Plantronics SupraPlus Noise-Canceling Headsets.
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