Plantronics S12 Headset System:
Convertible headset for over-the-head or over-the-ear
FireFly in-use indicator light
Volume and mute control
A/C Transformer – No batteries
No Quick Disconnect feature
Plantronics S12 Headset FAQ:
What is the standard setting for the Plantronics S12?
Can I use any other headset on my Plantronics S12 other than the one that came with the unit?
No, all you can use is the Firefly headset that is enclosed with the unit.