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Plantronics MX505 Mobile Headset (Black) for $5.99 Shipped

Plantronics MX505 Mobile Headset (Black) for $5.99 shipped.  Here is a screenshot for your reference.  This is a wired headset that fits phones with standard 2.5mm headset jack.  Note that at the time of this post, 90% of all user reviews have given it 4/5 and 5/5 ratings.  Note that it comes in OEM packaging, which means no pretty retail box and marketing materials but is otherwise identical.  Most places have it for about $23.