Adapter cable with 3.5mm Headset jack to RJ9 Desk Phones Jack for Avaya, Cisco and more. Connector 2: 3.5mm TRRS female. Connector 1: RJ9/RJ10/RJ22 male. 3 X Converter. Use PC Headset with most VOIP phones that have a RJ9/RJ10/RJ22 headset jack (Not compatible with RJ11).
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