Compatible with the following models: Avaya 9404, 9408, 9504, 9508, 9608, 9608G, 9610, 9611, 9611G, 9620, 9620C, 9620L, 9621 ,9621G, 9640, 9641, 9641G, 9641GS, 9650 and 9650C models. Compatible with Avaya IP office 9400, 9500, and 9600 Series Phones.
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