Audicom 2.5mm Headset to Cisco Phone Adapter - 2.5mm to RJ9/RJ10 IP Phone Jack Converter for Plantronics M22 Amplifier and Cisco Unified Telephone IP Phones 7931G 7940G 7941G 7942G 7945G (H25-CSA) 2.5mm headset adapter. Convert 2.5mm headset plug to your office phone with standard RJ port. Save money by buying standard phone headsets to use with your phone's headset jack Reduce clutter with single headset ONLY COMPATIBLE WITH SOME SPECIFIC CISCO UNIFIED IP PHONES: 7931G 7940 7940G 7941 7941G 7942 7942G 7945 7945G 7960 7960G 7961 7961G 7962 7962G 7965 7965G 7970 7970G 7971 7971G 7975 7975G 6921 6941 6945 6961 7821 7841 7861 8811 8841 8851 8861 8941 8945 8961 9951 9971 and Plantronics Amplifier: M10 M12 M22 & MX10 Vista Modular Adapters BUY THE ITEM TODAY IF YOU HAVE ONE OF THE PHONE OR AMPLIFIER MODELS LISTED ABOVE. NOT COMAPTIBLE WITH CISCO SPA SERIES