E52 Euphony wired earphones with wireless audio receiver, BT v5.0, 90mAh battery for 6 hours of calls/music and 200 hours of standby 1. Material: ABS. 2. BT 5.0, chip: Blue trum 5335B. 3. Battery capacity: 90mAh, charging time is about 2 hours. 4. Talk / music time: 6 hours. Standby