EPOS Adapt 160T USB II Wired Stereo Headset - Microsoft 1000901
User manual Sennheiser SC 160 USB (English - 2 pages)
Amazon.com: Sennheiser SC 160 USB (508315) - Double-Sided (Binaural) Headset for Business Professionals | with HD Stereo Sound, Noise Canceling Microphone, & USB Connector (Black), Black : Electronics