6000mAh 3.7v Battery bateria GSP1029102A for JBL Charge 3 (pls double check the place of 2 red wires on your old battery) - AliExpress Consumer Electronics
JBL Flip 4 Waterproof Portable Bluetooth Speakers, Squad, Rs.6460
User manual Jbl Charge CHARGE 3 SPECIAL EDITION Waterproof | manualsFile