Product model: F9 V5.0 Product color: black Bluetooth version: V5.0 Support protocol: HSP/HFP/ A2DP/AVRCP Working distance: straight line about 10M Song listening time: about 4-5 hours (single use when fully charged) Talk time: about 4-5 hours (single use at full power) Charging compartment battery capacity: 300mAh Charging compartment charging time: about 2H Headphone battery capacity: 50mAh*2 Headphone charging time: about 2H Supports one-key control, binaural HD calling, automatic power-on pairing, etc.