This product is either discontinued or we cannot get that from suppliers.
Plantronic 72442-41 HIS Adapter Cable, Black, Connector on First End 1 x Quick Disconnect Phone, Second End 1 x Male Phone, Compatibility Pantronics 9600 Phones, Device Phone, Conductor Copper.
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.