Product Specifications: * Battery Model: Charge 4 Waterproof Bluetooth Speaker * Battery Capacity: 7800mAh * Watt-hour: 28.26Wh * Voltage: 3.7V * Battery Type: Li-ion * Package: 1x 1INR19/66-3 battery, 1 set repair tool kits NOTE: 1. At the beginning, new battery is unstable and it will reach optimal performance after charging and discharging completely for 3-5 cycles. 2. If your Speaker has the battery indicate issue after install the battery, please try again firmly press the battery connector, make sure it connect perfectly, then reboot your speaker, the battery indicator will work correctly. 3. Please make sure the battery model matched with your device. If you are not sure, please send email to us with your battery details or pictures, we will give you professional suggestions. 4. We recommend you search video on YouTube to learn how to replace your battery in case to damage any of important cable. FAQ: Q1: Why the battery is not fully charged after installation? A1: For security, our battery is not full charged when leaving factory and testing. It’s normal situation. Q2: Why the new battery won’t charge? A2: Maybe bad connect, check the connector again and re-install it correctly. Q3: Why does the battery connector not fit? A3: Please check if you bought and received the wrong battery. You can check your model on the back of your Speaker.