Ultra-long battery life. Built-in high-capacity rechargeable lithium polymer batteryComfortable to wear. Ergonomically designed curvature, ear hooks fit your ears and your ears are well balancedWhen the headset is turned on and successfully connected to a phone or Bluetooth device with calling capabilities, you can make and receive calls. When an incoming call, the headset will alert you of an incoming call and the caller's number, contact the feature button once to answer the call, or double tap the feature button if you don't want to answer the call.Voice assistant: When the phone is connected, contact the function button for 1 second and release to activate the language assistant function. Universal for Android and .Comfortable in the hand: the surface is painted, as delicate and smooth as skin, you will love it with every pressProduct: Bluetooth headsetBluetooth version: V5.0+EDRWireless frequency: 2.4GHZSupport protocol: A2DP1.3/HFP1.6/HSP1.2/AVRCP1.6/D11.3Transmission distance: 10mBattery capacity: 50mAhCharging voltage/current: 5V/1APlayback/talk time: about 4 hoursCharging time: about 1 hourStandby time: 120 hoursSpeaker impedance: 8MM 32 ohmMicrophone sensitivity: -42DbWorking temperature: -10-50Charging bin parametersInput voltage/current: 5V/1ABattery capacity: 400mAhColour: blackMaterial: ABSSize: 145 x 81 x 25mmPackage Contents:1 x headphone1 x charging compartment1 x charging cableOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.