Extension Cable Adapter 3.5mm Male Jack to RJ9 4P4C Female Converter Wire for Cisco Telephone 0.35m；

Product Title

3.5mm TRRS Male to RJ9 4P4C Female Adapter Cable, Cisco‑Avaya Standard Wiring for IP Desk Phones

Full Product Description

3.5mm TRRS male to RJ9 (4P4C) female audio‑headset adapter cable, factory‑wired for Cisco and Avaya telephone pin‑out standard.

Designed to connect single‑jack TRRS headsets to Cisco, Avaya series IP desk phones for office / call‑center usage.

Important Note: Due to inconsistent internal wiring standards across different phone manufacturers, this adapter works for most Cisco/Avaya phones but is NOT 100% compatible with every telephone model on the market. Ordinary consumer‑grade TRRS headsets have lower impedance & power compared with dedicated professional telephone headsets. For optimal call‑audio quality, professional telephone‑purpose headsets are recommended.