Battery kit for APC Back UPS RS 1200/1500 replaces APCRBC109
APC Back-UPS Pro 1500VA 10-Outlet/2-USB Battery Back-Up and Surge Protector Black BN1500M2 - Best Buy
APC Back-UPS RS 1500 LCD BR1500LCD 12V 9Ah UPS Battery - This Is an AJC Brand Replacement - Walmart.com
Amazon.com: Beiter DC Power APC-UPS Backups RS1500 These Batteries are High Performance, Rechargeable (2)12V9ah Replacement for APC RBC109 : Automotive