Specifications: Bluetooth Version 5.0 + EDR Memory Card / TF Card Supported. Transmission Distance 10m Using Time: 20-40 hours Standby Time: 400 hours Battery Capacity: 200mAh Charging time: 4 hours Speaker Diameter: 400mm Range of Frequency: 20Hz-20KHz Feature: Classical leather earpad Improves the comfort of the pressure ear. Fold to Convenient storage. 4.1V lossless transmission. 3D Sound for your ear.