Global Teck Worldwide Intelligent Cord (4ft) for Plantronics, AddaSound Headsets | QD to RJ9 with Quick Disconnect | Compatible with Mitel, NEC, Aastra, Nortel, Shortel, Allworx, Cisco IMPROVED DESIGN: More ergonomic quick disconnect cable for Plantronics Headsets INTELLIGENT CORD: Compatible with Plantronics, AddaSound, VXi Tria-P, ProSet-P, Passport 10P/20P Headsets - works on various phones that have RJ-9/RJ-22 Headset port SAVE BIG: Replaces many different Plantronics cables - A10, U10, U10PS, HIC-1, Apollo and several others COMPATIBLE WITH MULTIPLE PHONES: Use with phones that have RJ9 headset ports such as Cisco, Mitel, NEC, Shoretel, Nortel, Meridian, Aastra, Toshiba, Polycom, Grandstream, Yealink, Allworx. The Inteli Cord has 9 settings for a wide range of compatibility...simply use the setting that works with your phone for optimal sound. REVIVE YOUR HEADSET: Is your Plantronics headset not sounding like when you purchased it. Try replacing the connecting cord first. Contact us if you have questions about compatibility with your phones.