S-TAG can interface between 3 communications devices, 2x HF, VHF, UHF radios or BLoS satellite PTT terminals, in any combination and any PTT over Cellular (PoC)/VoLTE solution running on a standard SmartPhone, such as Wave, Zello or any other suitable application that allows a remote audio accessory connection via its 3.5mm earpiece socket. Connection to SmartPhones can also be offered via USB (for compatible devices) or by Bluetooth, if a wireless connection to the SmartPhone is required.