Communication distance: about 20 meters (under barrier-free environment)Bluetooth version: V5.0+EDRHeadphone working time: about 3 hoursHeadphone standby time: about 50 hoursCharging time: about 2 hoursType of battery : Polymer lithium ion battery支持协议：HFP/HSP/A2DP/AVRCPSupport Agreement: HFP/HSP/A2DP/AVRCPHeadphone battery capacity: 3.7V 50mahHeadphone charging time: about 1 hourHeadphone compartment battery capacity: 3.7V 2000mahHeadphone compartment charging time: about 4 hoursNote: All technical information is subject to actual performance.Tips1.Please read the instructions carefully before using the product and keep it in a safe place.2.For the first time, please fully charge this product first.3.If the product has not been used for a long time (more than 1 month), please charge it4.You must select a charger from a regular manufacturer to charge it to avoid product damage.5.If the phone cannot search for a Bluetooth headset, make sure the Bluetooth headset is paired. If the mobile phone program is wrong, please restart the phone and try again; if the Bluetooth headset program is wrong, please restart the Bluetooth headset or restore the