Review on Wireless Bluetooth Microphone Compatible Accessories by Tara Taylor

Great option if your clip-on radio keeps breaking. Outstanding features (PERIOD) 12 hours Bluetooth operation, the microphone works 32 hours. (The control buttons on the microphone are only available when used with a smartphone.) It drains a "7.4V 1800mAh Li-Ion battery" faster than its typical estimated runtime of around 20 hours. 7.4V 3800mAh has 40 hours working time. The volume control will depend on your antenna and how well the radio is working. For example, if the radio volume is low or high, it mimics the volume of a microphone.