These are Foam Ear Cushions (qty 2) for use with Plantronics HW510 EncorePro, Plantronics HW510V EncorePro, Plantronics HW520 EncorePro and Plantronics HW520V EncorePro Headsets. Plantronics HW510V / HW510 / HW520V / HW520 EncorePro.
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