Amazon.com: Casil CA-1240 12V 4AH Multi Purpose Battery : Health & Household
Mighty Max Battery 12V 5Ah 4ah Alarm System Back Up Vista 20P ADT Rechargeable Sealed Lead Acid 1250 Backup Power Batteries in the Device Replacement Batteries department at Lowes.com
CASIL CA-1240 12V 4AH Rechargeable Sealed Lead Acid Alarm Battery