Speaker Battery 7.4V/5200mAh/6800mAh GSP-2S2P-XT3A for JBL Xtreme 3 - AliExpress
Restored JBLXtreme 3: Portable Speaker with Bluetooth, Built-in Battery, Waterproof and Dustproof Feature, and Charge Out - Blue, (Refurbished) - Walmart.com
JBL XTREME 3 Portable Waterproof Dustproof Bluetooth Speaker with Buil
Speaker Battery IBA001GA ID1019 for JBL Xtreme 2 JBL Xtreme 3 Xtreme2 Xtreme3 Wireless Bluetooth Speaker Battery - AliExpress
Amazon.com: Youejoeq 6800mAh High-Capacity Extended Replacement Battery for JBL Xtreme 3 Wireless Bluetooth Speaker, fits Part no GSP-2S2P-XT3A : Electronics