Cordless headset accessory for the eristerminal vsp725a and vsp735a sip desksets only note accessory headset only requires a vsp725 entry level deskset or vsp735 feature deskset to operate multiple wearing styles answer and end calls from the headset mute and volume controls noise cancelling 3 year warranty headphones headphone type multiple wearing styles cordedcordless cordless volume control yes microphone noise cancelling yes mute swi