Inspire your senses:Inspire yourself by rich stereo sound with the Audsom M04 [upgrade version] headphonesDeep Bass and full range soundCan be used both wired and wirelessComfortable, lightweight fit for long-term wearingEasily adjust audio and phone call Product Features:Deep bass and full range sound for a superior audio experienceSuperior audio experience for both listening and phone callFull range Frequency Responses (20Hz-20kHz) for rich bassMini high sensitivity microphone enhances speech accuracy and clear voice transmissions Comfortable, lightweight fit for long-term wearingOver-the-ear design, with soft ear cushionsStretch headband for any head sizeAdjust ear cups for any storage needsLightweight design at7oz/200g Easy to adjust audio & phone call and long play-timeBuilt-In mic for headset functionality with controls for media and phone calls400Am rechargeable battery guarantees 18 hours play-time Technical Specifications:Bluetooth v3.0Play time:18 hoursStandby time 250 hoursCharging time: 2-3 hoursSpeaker diameter: 40mmSensitivity: 103??3dBImpedance: 64?? Package Included:Ausdom M04 HeadsetUSB Charging Cable3.5mm Audio cable (4feet / 1.2m) User manual