Review on 🔊 Beyerdynamic PHONUM Bluetooth/USB Speakerphone - 360° Voice-Tracking with Beamforming Mics, Active Noise Cancelling, Zoom Compatible, 12 Hour Battery - Ideal for All Major Platforms and Hardware by Kara Davis

I ordered two (one replacing the other) as Revain manages the stock. The battery of the first did not hold a charge (the problem was noted in at least one other review). The second could not be switched on at all even after 12 hours of charging. You might have better luck buying new ones, but I think these were returned because they didn't work to begin with. So there's a risk that "new" ones won't work, and reassurance that Revain doesn't test returns before reselling them.