The Heil AD-1-C is a headset adapter cable which allows you to interface your Heil headset with to your Collins/Drake transceiver! The AD-1-C cable is required for Heil boom microphone headset models including PROSET Elite, PROSET, the original and reintroduced PRO-MICRO series and BM-10 series headsets, and the legacy PROSET PLUS and QUIET PHONE.
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