Mighty Max Battery ML4-6- 6 VOLT 4.5 AH SLA BATTERY- 6 PACK Rechargeable Sealed Lead Acid 645 Alarm System Batteries (6-Pack) in the Device Replacement Batteries department at Lowes.com
Dare 3476 6V 4.5Ah Battery for DS 20 Solar Fence Charger | eBay
6 Volt 4.5 Ah Sealed Lead Acid Rechargeable Battery - 2 Pack | Battery Mart