hifiman deva over-ear full-size open-back planar magnetic headphone with bluetooth dongle/receiver, balanced input, easily switch to wireless, usb/wireless/wired hifiman </b>deva headphone specifications<b> <br>frequency response: 20-20khz <br>impedance: 18ω <br>sensitivity: 93.5db <br>weight: 360g <br>socket: trrs 3.5mm </b>bluemini specifications:<b> <br>frequency response: 20hz-20khz <br>amp output in fact 230mw <br>amp output in theory: 1125mw <br>tdh: <0.1%@1w/1khz <br>snr:95db <br>battery life: 7-10hours (bluetooth) <br>weight: 25g <br>bluetooth codecs: ldac, aptx-hd, aptx, aac, sbc <br>transmission: bluetooth/usb type c </b>what’s included:<b> <br>headphone x1 <br>bluemini x1 <br>usb charging cable x1 <br>headphone cable 3.5mm x1 <br>3.5mm to 6.35mm adapter x1 <br>user manual x1 <br>warranty card x1