Please note that you need to purchase the correct respective cord that will be suitable for your particular phone system. Let us know your make and model, (e.g. Cisco 7940 or NEC DTP32D) so we can let you know which cord is needed.
This model comes with a 'direct connect cord', but your phone system may require a different cord.
Wideband Binaural Headset with Noise Cancelling Microphone. - comes with direct connect cord.