Hi- Another option is to look for/make the cable that connects directly to terminals inside the phone. The Adapter you're looking at only works for 6 button 565HK sets; You have to use the cable shown in the pic for 10 button, Call director or single line sets. Most of those BSPs have wiring diagrams to wire in the cable. The Transmitter, power and speaker all plug into the amphenol cable.

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