Ultra-long battery life. Built-in high-capacity rechargeable lithium polymer battery Comfortable to wear. Ergonomically designed curvature, ear hooks fit your ears and your ears are well balanced When 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 press Product: Bluetooth headset Bluetooth version: V 5.0+ Wireless frequency: 2.4GHZ Support protocol: A2DP 1.3/HFP 1.6/HSP 1.2/AVRCP 1.6/D 11.3 Transmission distance: 10m Battery capacity: 50mAh Charging voltage/current: 5V/1A Playback/talk time: about 4 hours Charging time: about 1 hour Standby time: 120 hours Speaker impedance: 8MM 32 ohm Microphone sensitivity: -42Db Working temperature: -10-50 Charging bin parameters Input voltage/current: 5V/1A Battery capacity: 400mAh Colour: black Material: ABS Size: 145 x 81 x 25mm Package Contents: 1 x headphone 1 x charging compartment 1 x charging cable Only 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.