DW20 USB – AUS (Single Connectivity) DW Pro 1 – DECT Monaural Wireless Headset with base station for PC Only If using Skype for Business, use the Sennheiser DW Pro 1 USB ML which is optimized for use with Microsoft Lync. This headset comes in a Binaural version: the Sennheiser DW Pro 2 USB. To connect to a desk phone only, the Sennheiser DW Pro 1 PHONE is more suitable. For a headset that connects to both the deskphone and PC, the Sennheiser DW Pro 1 is more suitable. Buy mow:- https://www.headsetsonly.com.au/shop/sennheiser-dw-pro-1-monaural-usb-wireless-headset-dw20-usb/