Hidden microphone, with bluetooth-compatible connectivity dialogue, you can conveniently answer the phone.Enjoy stereo music wirelessly from bluetooth-compatible devices.You will get superior comfort as the headband is adjustable.Item Name: bluetooth-compatible HeadsetMaterial: PlasticBluetooth Version: 4.1Frequency Range: 2.4GTrumpet: 40Trumpet Average Sensitivity: 105dB (AT 1KHZ + 3dB)Frequency Response Range: 20Hz - 20KHzMain Chip: V4.0 + EDRBattery: Rechargeable Lithium Polymer Battery (Included)Battery Voltage: 3.7VCall Duration: About 14 HoursWorking Time: About 250 HoursSupport Equipment: Mobile Phone, Tablet Computer, Notebook, Game ConsoleSupport Software: Mobile Phone Default Player, for KuGoo, for TTPlayer, for Baidu Music, for TTPodFeatures: Comfortable to Wear, Stereo Sound, Foldable, WirelessLength: 160mm/6.3& 39;& 39; (Approx.)Width: 75mm/2.95& 39;& 39; (Approx.)Height: 170mm/6.69& 39;& 39; (Approx.)Notes:Due to the light and screen setting difference, the item& 39;s color may be slightly different from the pictures.Please allow slight dimension difference due to different manual measurement.Package Includes:1 x bluetooth-compatible Headset1 x 3.5mm Audio Cable1 x USB Data Cable1 x User Manual