Amazon.com: 6volt 7.2ah Battery Replacement for WKA6-7.2F : Health & Household
MIGHTY MAX BATTERY 6V 7.2Ah SLA0925 NP7-6 PWRBC67 KB670 SLA Battery - 4 Pack MAX3438188 - The Home Depot
Mighty Max Battery 6volt 7.2ah Battery Replacement for WKA6-7.2F Rechargeable Sealed Lead Acid 670 Backup Power Batteries in the Device Replacement Batteries department at Lowes.com