Superior-quality Heil Sound Microphone Adapter Cables are used to interface your Heil microphone to your favorite transceiver. These cables are available for all Heil microphones. Most cables feature the 4-pin XLR connectors that support a built-in PTT switch, including Classic, Goldline, GM, Genisis, Handi-Mic, HM-12, and HM-10 microphones. Those cables that include "XLR" in the part number feature the 3-pin XLR connector used with the PRO Series microphones, which require the use of an outboard PTT or foot switch, such as the PR-20, PR-28, PR-40, and PR-781.