Operation voltagev30v 42 modelbh 01 input voltage v37 cable lengthcm50cm power supply37v materialaluminium metal rubber plastic typeneckband general usesports fitness functionvolume control with microphone bluetooth noise cancelling sports communicationwireless bluetooth connectorsusb memory capacitynone speaker diameter12mm speaker sensitivitydb983db speaker frequency response20hz 20khz microphone unit4mmx15mm microphone spl383db10w01m mic