Amazon.com: ExpertPower 6 Volt 4.5 Amp Rechargeable Battery (EXP645) : Tools & Home Improvement
Mighty Max Battery 6V 4.5AH SLA Multipurpose Rechargeable Battery Rechargeable Sealed Lead Acid 645 Backup Power Batteries in the Device Replacement Batteries department at Lowes.com
Amazon.com: ExpertPower 6 Volt 4.5 Amp Rechargeable Battery (4 Pack) : Health & Household