HW261N & Avaya SupraElite AH450, AH450N, AH460, AH460N, AW450N. Plantronics SupraPlus H251, H251N, H261, H261N, HW251, HW251N, HW261. SupraPlus Receiver Assembly. (a.k.a. SupraPlus Receiver). It is for Plantronics SupraPlus & Avaya SupraElite headsets.
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