The Poly Voyager 4320 UC (218475-02) are professional stereo wireless headphones designed for office and smart working: they offer Bluetooth 5.x connection with USB-A dongle (Poly BT700), wide autonomy for calls and playback, and on-ear commands for call and volume management. They are suitable for long-lasting and stable connectivity without advanced ANC. Reported defects: relatively high weight for prolonged use, absence of ANC and, in some batches, less soft ear pads than higher models. Main technical specifications Connectivity: Bluetooth (version 5.x) + USB-A receiver (Poly BT700) for quick pairing and UC compatibility. Autonomy: up to 24 hours of talk time and many hours of playback (declared up to ~47 h listening in some sources). Wireless capacity: up to ~50 m (164 ft) in free field with dongle. Audio driver: over-ear stereo pavilions designed for voice and multimedia (balanced sound for calls). Microphone: double microphone/boom or built-in array for clarity in office environments; management calls via on-ear keys. Charging time: fast charging (e.g. 15 min for significant hours of use) and full cycle in about 1.6 h according to datasheet/reviews. Certifications/compatibility UC: certified versions for Microsoft Teams/UC available (check the MS/UC SKU).