Plantronics EncorePro HW510V (510V) has a clear voice tube boom and is a single ear (monaural) over-the-head headset. It does NOT have a noise canceling microphone. Plantronics HW510V is constructed with tough metal joints so it's built with durability and it extends the life of the headset. HW510V ends in a Plantronics QD (quick disconnect), so it's compatible with all of the Plantronics bottom cables so it's adaptable to just able any phone or computer on the market.. Plantronics M22 is for professionals—particularly VoIP users—the Plantronics M22 Vista amplifier delivers precise levels of listening comfort, sophisticated hearing protection, and superior audio performance. The Plantronics Vista M22 includes Clearline™ audio to improve call quality in any environment, especially wideband.
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