The D1 USB dongle bundled with the SDW 30 HS headset. Single-sided DECT headset with ultra noise cancelling mic, mute button on the mic boom, not convertible. Super wideband audio capable. Headset pouch and charge cable included. KEY FEATURES : Make your DECT headset mobile Neat, plug-and-play solution, no base station necessary Single-sided wearing style Pack and protect your headset Broad compatibility