Amazon.com: USB to 2.5mm,Ancable Replacement USB Charging Cable (3ft / 1m) for JBL E40BT E50BT J56BT Headphones (Black) : Electronics
Amazon.com: 60cm USB to 2.5mm Jack Charge Cable for Synchros S300 S300I S300a S500 S700 S400BT J56BT E40BT E30 E40 E50BT S400BT Headphones : Electronics
Amazon.com: SCOVEE USB to 2.5mm Male AUX Audio Jack Charging Cable for JBL Synchros S300 S300I S300a S400BT J56BT E40BT E30 E40 E50BT S500 S700 Headphones Stereo Power Wire for JBL Charger
Replacement USB Charging Cable for JBL Synchros E40BT/E50BT/J56BT Headphones 2.5mm – Ancable
2.5mm USB charging charger cable for JBL Synchros E40BT/E50BT/J56BT Headphones USB charge|Data Cables| - AliExpress