Headset adapter cable. Plugs into modular phone jack. To take advantage of the full wideband audio that is offered with the 9600 phones, use the HIS Adapter Cable with your wideband headset. Quick Disconnect (QD) capability allows the headset to detach without losing the call. Coiled lightweight cord connects any H-Series headset with Quick-Disconnect plug to compatible Plantronics amplifiers, or phones with compatible headset ports.