Bluetooth V4.2. Distance: 10 m range of frequency: 2.4 to 2.4835Ghz. ISM band BT sensitivity 98dB + 3dB. Music format: MP3/WMA. Rechargeable lithium battery: 100mAh. Type: stereo prixton headphone with MIC Speaker: ø 13 mm. Sensitivity: 115dB S.P.L at 1KHZ. Impedance: 16 Ω Frequency, response: 20HZ-20.000KHZ. Rated Power 40mW. Power capability: 100mW. Receiver distance <100 meters, standby time 200 hours. Plastic, PU Plastic.