The ACN-01 consists of a PTT and microphone controller and can be used with several different Hytera earphones: ES-01, ES-02, EH-01, EH-02. It is protected against dust and moisture according to IP54. Furthermore, the ACN-01 supports the VOX function, if enabled in the radio. Those earphones can be connected to the ACN-01 via the 3.5-mm jack plug. This concept allows to replace the earphones fast and easily. In case of a malfunction, it is not necessary to replace the whole audio set.