SPECIFICATIONS: Item: XIAOMI MI POCOPHONE F1 - BM4E Capacity: 3900mAh Cell Grade: AAA/AAA+/AAAA Built In/Out: BUILT IN Certification: CE,RoHS,MSDS,PSE,FCC Limit Voltage: 4.2V Warranty: 1 week Cell Type: DOUBLE IC, Li-iON BATTERY Standby Time: 72 hours - 120 hours Talking Time: 5 hours - 11 hours Cycle Life: >500times Working Temperature: -15 to 50 degrees C°