Amazon.com: High Capacity Replacement Battery + Tool for JBL Flip 4 Speaker or Special Edition Model GSP872693 Li-Polymer 3.70V 3000mAh/11.10Wh Repair Power : Electronics
JBL Flip4 Firmware Update (how to) - YouTube
Reverse-engineering JBL flip 4 | Hackaday.io
How to update the JBL Charge / Flip 3, 4 and 5 firmware? – alfanoTV
JBL Flip 4 Firmware Update Instructions - Tom's Tek Stop
Can't Update my JBL Flip 4 Firmware to 3.9.0. Any help would be appreciated 🙂 : r/JBL