*DISCONTINUED* by Plantronics. No longer available.
This is the Plantronics S11 replacement/spare headset. This headset plugs directly into Plantronics S11 base with modular (square) RJ-9 plug. This headset is the replacement for your existing S11 system only. It will NOT work with any other Plantronics amplifier.
If you wish to have a different headset for the S11 (ie. binaural headset), you can use any Plantronics H-series headsets + Plantronics U10P cable