JBL Partybox 300 - Running on a Lawnmower Battery - YouTube
MPF Products 13400mAh Extended SUN-INTE-125, 2INR19/66/4 Battery Replacement Compatible with JBL PartyBox 300 High Power Portable Wireless Bluetooth Party Speaker - Newegg.com
JBL Partybox 300 Audio Repair Services - Get It Fixed