POLY Sync 20. Device type: Universal, Product colour: Black, Silver, Control type: Buttons, Touch. Frequency range: 80 - 20000 Hz. Microphone frequency: 100 - 6700 Hz. Connectivity technology: Wired & Wireless, Interface: Bluetooth, Bluetooth profiles: A2DP, AVRCP, HFP. Power source type: Battery, Battery technology: Lithium-Ion (Li-Ion), Battery capacity: 3200 mAh